Adding upstream version 86.0.1.upstream/86.0.1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

26 files changed, 3218 insertions, 0 deletions

diff --git a/devtools/client/shared/sourceeditor/codemirror/addon/accessibleTextarea.js b/devtools/client/shared/sourceeditor/codemirror/addon/accessibleTextarea.js
new file mode 100644
index 0000000000..2ab63977f8
--- /dev/null
+++ b/devtools/client/shared/sourceeditor/codemirror/addon/accessibleTextarea.js
@@ -0,0 +1,146 @@
+/*
+ * Copyright (C) 2012 Google Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+(function(mod) {
+  mod(require("devtools/client/shared/sourceeditor/codemirror/lib/codemirror"));
+})(function(CodeMirror) {
+  // CodeMirror uses an offscreen <textarea> to detect input.
+  // Due to inconsistencies in the many browsers it supports, it simplifies things by
+  // regularly checking if something is in the textarea, adding those characters to the
+  // document, and then clearing the textarea.
+  // This breaks assistive technology that wants to read from CodeMirror, because the
+  // <textarea> that they interact with is constantly empty.
+  // Because we target up-to-date Firefox, we can guarantee consistent input events.
+  // This lets us leave the current line from the editor in our <textarea>.
+  // CodeMirror still expects a mostly empty <textarea>, so we pass CodeMirror a fake
+  // <textarea> that only contains the users input.
+  CodeMirror.inputStyles.accessibleTextArea = class extends CodeMirror.inputStyles.textarea {
+    /**
+     * @override
+     * @param {!Object} display
+     */
+    init(display) {
+      super.init(display);
+      this.textarea.addEventListener("compositionstart",
+        this._onCompositionStart.bind(this));
+    }
+
+    _onCompositionStart() {
+      if (this.textarea.selectionEnd === this.textarea.value.length) {
+        return;
+      }
+
+      // CodeMirror always expects the caret to be at the end of the textarea
+      // When in IME composition mode, clip the textarea to how CodeMirror expects it,
+      // and then let CodeMirror do its thing.
+      this.textarea.value = this.textarea.value.substring(0, this.textarea.selectionEnd);
+      const length = this.textarea.value.length;
+      this.textarea.setSelectionRange(length, length);
+      this.prevInput = this.textarea.value;
+    }
+
+    /**
+     * @override
+     * @param {Boolean} typing
+     */
+    reset(typing) {
+      if (
+        typing ||
+        this.contextMenuPending ||
+        this.composing ||
+        this.cm.somethingSelected()
+      ) {
+        super.reset(typing);
+        return;
+      }
+
+      // When navigating around the document, keep the current visual line in the textarea.
+      const cursor = this.cm.getCursor();
+      let start, end;
+      if (this.cm.options.lineWrapping) {
+        // To get the visual line, compute the leftmost and rightmost character positions.
+        const top = this.cm.charCoords(cursor, "page").top;
+        start = this.cm.coordsChar({left: -Infinity, top});
+        end = this.cm.coordsChar({left: Infinity, top});
+      } else {
+        // Limit the line to 1000 characters to prevent lag.
+        const offset = Math.floor(cursor.ch / 1000) * 1000;
+        start = {ch: offset, line: cursor.line};
+        end = {ch: offset + 1000, line: cursor.line};
+      }
+
+      this.textarea.value = this.cm.getRange(start, end);
+      const caretPosition = cursor.ch - start.ch;
+      this.textarea.setSelectionRange(caretPosition, caretPosition);
+      this.prevInput = this.textarea.value;
+    }
+
+    /**
+     * @override
+     * @return {boolean}
+     */
+    poll() {
+      if (this.contextMenuPending || this.composing) {
+        return super.poll();
+      }
+
+      const text = this.textarea.value;
+      let start = 0;
+      const length = Math.min(this.prevInput.length, text.length);
+
+      while (start < length && this.prevInput[start] === text[start]) {
+        ++start;
+      }
+
+      let end = 0;
+
+      while (
+        end < length - start &&
+        this.prevInput[this.prevInput.length - end - 1] === text[text.length - end - 1]
+      ) {
+        ++end;
+      }
+
+      // CodeMirror expects the user to be typing into a blank <textarea>.
+      // Pass a fake textarea into super.poll that only contains the users input.
+      const placeholder = this.textarea;
+      this.textarea = document.createElement("textarea");
+      this.textarea.value = text.substring(start, text.length - end);
+      this.textarea.setSelectionRange(
+        placeholder.selectionStart - start,
+        placeholder.selectionEnd - start
+      );
+      this.prevInput = "";
+      const result = super.poll();
+      this.prevInput = text;
+      this.textarea = placeholder;
+      return result;
+    }
+  };
+});
diff --git a/devtools/client/shared/sourceeditor/codemirror/addon/comment/comment.js b/devtools/client/shared/sourceeditor/codemirror/addon/comment/comment.js
new file mode 100644
index 0000000000..b3a3e93689
--- /dev/null
+++ b/devtools/client/shared/sourceeditor/codemirror/addon/comment/comment.js
@@ -0,0 +1,209 @@
+// CodeMirror, copyright (c) by Marijn Haverbeke and others
+// Distributed under an MIT license: https://codemirror.net/LICENSE
+
+(function(mod) {
+  if (typeof exports == "object" && typeof module == "object") // CommonJS
+    mod(require("devtools/client/shared/sourceeditor/codemirror/lib/codemirror"));
+  else if (typeof define == "function" && define.amd) // AMD
+    define(["../../lib/codemirror"], mod);
+  else // Plain browser env
+    mod(CodeMirror);
+})(function(CodeMirror) {
+  "use strict";
+
+  var noOptions = {};
+  var nonWS = /[^\s\u00a0]/;
+  var Pos = CodeMirror.Pos;
+
+  function firstNonWS(str) {
+    var found = str.search(nonWS);
+    return found == -1 ? 0 : found;
+  }
+
+  CodeMirror.commands.toggleComment = function(cm) {
+    cm.toggleComment();
+  };
+
+  CodeMirror.defineExtension("toggleComment", function(options) {
+    if (!options) options = noOptions;
+    var cm = this;
+    var minLine = Infinity, ranges = this.listSelections(), mode = null;
+    for (var i = ranges.length - 1; i >= 0; i--) {
+      var from = ranges[i].from(), to = ranges[i].to();
+      if (from.line >= minLine) continue;
+      if (to.line >= minLine) to = Pos(minLine, 0);
+      minLine = from.line;
+      if (mode == null) {
+        if (cm.uncomment(from, to, options)) mode = "un";
+        else { cm.lineComment(from, to, options); mode = "line"; }
+      } else if (mode == "un") {
+        cm.uncomment(from, to, options);
+      } else {
+        cm.lineComment(from, to, options);
+      }
+    }
+  });
+
+  // Rough heuristic to try and detect lines that are part of multi-line string
+  function probablyInsideString(cm, pos, line) {
+    return /\bstring\b/.test(cm.getTokenTypeAt(Pos(pos.line, 0))) && !/^[\'\"\`]/.test(line)
+  }
+
+  function getMode(cm, pos) {
+    var mode = cm.getMode()
+    return mode.useInnerComments === false || !mode.innerMode ? mode : cm.getModeAt(pos)
+  }
+
+  CodeMirror.defineExtension("lineComment", function(from, to, options) {
+    if (!options) options = noOptions;
+    var self = this, mode = getMode(self, from);
+    var firstLine = self.getLine(from.line);
+    if (firstLine == null || probablyInsideString(self, from, firstLine)) return;
+
+    var commentString = options.lineComment || mode.lineComment;
+    if (!commentString) {
+      if (options.blockCommentStart || mode.blockCommentStart) {
+        options.fullLines = true;
+        self.blockComment(from, to, options);
+      }
+      return;
+    }
+
+    var end = Math.min(to.ch != 0 || to.line == from.line ? to.line + 1 : to.line, self.lastLine() + 1);
+    var pad = options.padding == null ? " " : options.padding;
+    var blankLines = options.commentBlankLines || from.line == to.line;
+
+    self.operation(function() {
+      if (options.indent) {
+        var baseString = null;
+        for (var i = from.line; i < end; ++i) {
+          var line = self.getLine(i);
+          var whitespace = line.slice(0, firstNonWS(line));
+          if (baseString == null || baseString.length > whitespace.length) {
+            baseString = whitespace;
+          }
+        }
+        for (var i = from.line; i < end; ++i) {
+          var line = self.getLine(i), cut = baseString.length;
+          if (!blankLines && !nonWS.test(line)) continue;
+          if (line.slice(0, cut) != baseString) cut = firstNonWS(line);
+          self.replaceRange(baseString + commentString + pad, Pos(i, 0), Pos(i, cut));
+        }
+      } else {
+        for (var i = from.line; i < end; ++i) {
+          if (blankLines || nonWS.test(self.getLine(i)))
+            self.replaceRange(commentString + pad, Pos(i, 0));
+        }
+      }
+    });
+  });
+
+  CodeMirror.defineExtension("blockComment", function(from, to, options) {
+    if (!options) options = noOptions;
+    var self = this, mode = getMode(self, from);
+    var startString = options.blockCommentStart || mode.blockCommentStart;
+    var endString = options.blockCommentEnd || mode.blockCommentEnd;
+    if (!startString || !endString) {
+      if ((options.lineComment || mode.lineComment) && options.fullLines != false)
+        self.lineComment(from, to, options);
+      return;
+    }
+    if (/\bcomment\b/.test(self.getTokenTypeAt(Pos(from.line, 0)))) return
+
+    var end = Math.min(to.line, self.lastLine());
+    if (end != from.line && to.ch == 0 && nonWS.test(self.getLine(end))) --end;
+
+    var pad = options.padding == null ? " " : options.padding;
+    if (from.line > end) return;
+
+    self.operation(function() {
+      if (options.fullLines != false) {
+        var lastLineHasText = nonWS.test(self.getLine(end));
+        self.replaceRange(pad + endString, Pos(end));
+        self.replaceRange(startString + pad, Pos(from.line, 0));
+        var lead = options.blockCommentLead || mode.blockCommentLead;
+        if (lead != null) for (var i = from.line + 1; i <= end; ++i)
+          if (i != end || lastLineHasText)
+            self.replaceRange(lead + pad, Pos(i, 0));
+      } else {
+        self.replaceRange(endString, to);
+        self.replaceRange(startString, from);
+      }
+    });
+  });
+
+  CodeMirror.defineExtension("uncomment", function(from, to, options) {
+    if (!options) options = noOptions;
+    var self = this, mode = getMode(self, from);
+    var end = Math.min(to.ch != 0 || to.line == from.line ? to.line : to.line - 1, self.lastLine()), start = Math.min(from.line, end);
+
+    // Try finding line comments
+    var lineString = options.lineComment || mode.lineComment, lines = [];
+    var pad = options.padding == null ? " " : options.padding, didSomething;
+    lineComment: {
+      if (!lineString) break lineComment;
+      for (var i = start; i <= end; ++i) {
+        var line = self.getLine(i);
+        var found = line.indexOf(lineString);
+        if (found > -1 && !/comment/.test(self.getTokenTypeAt(Pos(i, found + 1)))) found = -1;
+        if (found == -1 && nonWS.test(line)) break lineComment;
+        if (found > -1 && nonWS.test(line.slice(0, found))) break lineComment;
+        lines.push(line);
+      }
+      self.operation(function() {
+        for (var i = start; i <= end; ++i) {
+          var line = lines[i - start];
+          var pos = line.indexOf(lineString), endPos = pos + lineString.length;
+          if (pos < 0) continue;
+          if (line.slice(endPos, endPos + pad.length) == pad) endPos += pad.length;
+          didSomething = true;
+          self.replaceRange("", Pos(i, pos), Pos(i, endPos));
+        }
+      });
+      if (didSomething) return true;
+    }
+
+    // Try block comments
+    var startString = options.blockCommentStart || mode.blockCommentStart;
+    var endString = options.blockCommentEnd || mode.blockCommentEnd;
+    if (!startString || !endString) return false;
+    var lead = options.blockCommentLead || mode.blockCommentLead;
+    var startLine = self.getLine(start), open = startLine.indexOf(startString)
+    if (open == -1) return false
+    var endLine = end == start ? startLine : self.getLine(end)
+    var close = endLine.indexOf(endString, end == start ? open + startString.length : 0);
+    var insideStart = Pos(start, open + 1), insideEnd = Pos(end, close + 1)
+    if (close == -1 ||
+        !/comment/.test(self.getTokenTypeAt(insideStart)) ||
+        !/comment/.test(self.getTokenTypeAt(insideEnd)) ||
+        self.getRange(insideStart, insideEnd, "\n").indexOf(endString) > -1)
+      return false;
+
+    // Avoid killing block comments completely outside the selection.
+    // Positions of the last startString before the start of the selection, and the first endString after it.
+    var lastStart = startLine.lastIndexOf(startString, from.ch);
+    var firstEnd = lastStart == -1 ? -1 : startLine.slice(0, from.ch).indexOf(endString, lastStart + startString.length);
+    if (lastStart != -1 && firstEnd != -1 && firstEnd + endString.length != from.ch) return false;
+    // Positions of the first endString after the end of the selection, and the last startString before it.
+    firstEnd = endLine.indexOf(endString, to.ch);
+    var almostLastStart = endLine.slice(to.ch).lastIndexOf(startString, firstEnd - to.ch);
+    lastStart = (firstEnd == -1 || almostLastStart == -1) ? -1 : to.ch + almostLastStart;
+    if (firstEnd != -1 && lastStart != -1 && lastStart != to.ch) return false;
+
+    self.operation(function() {
+      self.replaceRange("", Pos(end, close - (pad && endLine.slice(close - pad.length, close) == pad ? pad.length : 0)),
+                        Pos(end, close + endString.length));
+      var openEnd = open + startString.length;
+      if (pad && startLine.slice(openEnd, openEnd + pad.length) == pad) openEnd += pad.length;
+      self.replaceRange("", Pos(start, open), Pos(start, openEnd));
+      if (lead) for (var i = start + 1; i <= end; ++i) {
+        var line = self.getLine(i), found = line.indexOf(lead);
+        if (found == -1 || nonWS.test(line.slice(0, found))) continue;
+        var foundEnd = found + lead.length;
+        if (pad && line.slice(foundEnd, foundEnd + pad.length) == pad) foundEnd += pad.length;
+        self.replaceRange("", Pos(i, found), Pos(i, foundEnd));
+      }
+    });
+    return true;
+  });
+});
diff --git a/devtools/client/shared/sourceeditor/codemirror/addon/comment/continuecomment.js b/devtools/client/shared/sourceeditor/codemirror/addon/comment/continuecomment.js
new file mode 100644
index 0000000000..56a8284ed1
--- /dev/null
+++ b/devtools/client/shared/sourceeditor/codemirror/addon/comment/continuecomment.js
@@ -0,0 +1,78 @@
+// CodeMirror, copyright (c) by Marijn Haverbeke and others
+// Distributed under an MIT license: https://codemirror.net/LICENSE
+
+(function(mod) {
+  if (typeof exports == "object" && typeof module == "object") // CommonJS
+    mod(require("devtools/client/shared/sourceeditor/codemirror/lib/codemirror"));
+  else if (typeof define == "function" && define.amd) // AMD
+    define(["../../lib/codemirror"], mod);
+  else // Plain browser env
+    mod(CodeMirror);
+})(function(CodeMirror) {
+  function continueComment(cm) {
+    if (cm.getOption("disableInput")) return CodeMirror.Pass;
+    var ranges = cm.listSelections(), mode, inserts = [];
+    for (var i = 0; i < ranges.length; i++) {
+      var pos = ranges[i].head
+      if (!/\bcomment\b/.test(cm.getTokenTypeAt(pos))) return CodeMirror.Pass;
+      var modeHere = cm.getModeAt(pos)
+      if (!mode) mode = modeHere;
+      else if (mode != modeHere) return CodeMirror.Pass;
+
+      var insert = null;
+      if (mode.blockCommentStart && mode.blockCommentContinue) {
+        var line = cm.getLine(pos.line).slice(0, pos.ch)
+        var end = line.lastIndexOf(mode.blockCommentEnd), found
+        if (end != -1 && end == pos.ch - mode.blockCommentEnd.length) {
+          // Comment ended, don't continue it
+        } else if ((found = line.lastIndexOf(mode.blockCommentStart)) > -1 && found > end) {
+          insert = line.slice(0, found)
+          if (/\S/.test(insert)) {
+            insert = ""
+            for (var j = 0; j < found; ++j) insert += " "
+          }
+        } else if ((found = line.indexOf(mode.blockCommentContinue)) > -1 && !/\S/.test(line.slice(0, found))) {
+          insert = line.slice(0, found)
+        }
+        if (insert != null) insert += mode.blockCommentContinue
+      }
+      if (insert == null && mode.lineComment && continueLineCommentEnabled(cm)) {
+        var line = cm.getLine(pos.line), found = line.indexOf(mode.lineComment);
+        if (found > -1) {
+          insert = line.slice(0, found);
+          if (/\S/.test(insert)) insert = null;
+          else insert += mode.lineComment + line.slice(found + mode.lineComment.length).match(/^\s*/)[0];
+        }
+      }
+      if (insert == null) return CodeMirror.Pass;
+      inserts[i] = "\n" + insert;
+    }
+
+    cm.operation(function() {
+      for (var i = ranges.length - 1; i >= 0; i--)
+        cm.replaceRange(inserts[i], ranges[i].from(), ranges[i].to(), "+insert");
+    });
+  }
+
+  function continueLineCommentEnabled(cm) {
+    var opt = cm.getOption("continueComments");
+    if (opt && typeof opt == "object")
+      return opt.continueLineComment !== false;
+    return true;
+  }
+
+  CodeMirror.defineOption("continueComments", null, function(cm, val, prev) {
+    if (prev && prev != CodeMirror.Init)
+      cm.removeKeyMap("continueComment");
+    if (val) {
+      var key = "Enter";
+      if (typeof val == "string")
+        key = val;
+      else if (typeof val == "object" && val.key)
+        key = val.key;
+      var map = {name: "continueComment"};
+      map[key] = continueComment;
+      cm.addKeyMap(map);
+    }
+  });
+});
diff --git a/devtools/client/shared/sourceeditor/codemirror/addon/dialog/dialog.css b/devtools/client/shared/sourceeditor/codemirror/addon/dialog/dialog.css
new file mode 100644
index 0000000000..677c078387
--- /dev/null
+++ b/devtools/client/shared/sourceeditor/codemirror/addon/dialog/dialog.css
@@ -0,0 +1,32 @@
+.CodeMirror-dialog {
+  position: absolute;
+  left: 0; right: 0;
+  background: inherit;
+  z-index: 15;
+  padding: .1em .8em;
+  overflow: hidden;
+  color: inherit;
+}
+
+.CodeMirror-dialog-top {
+  border-bottom: 1px solid #eee;
+  top: 0;
+}
+
+.CodeMirror-dialog-bottom {
+  border-top: 1px solid #eee;
+  bottom: 0;
+}
+
+.CodeMirror-dialog input {
+  border: none;
+  outline: none;
+  background: transparent;
+  width: 20em;
+  color: inherit;
+  font-family: monospace;
+}
+
+.CodeMirror-dialog button {
+  font-size: 70%;
+}
diff --git a/devtools/client/shared/sourceeditor/codemirror/addon/dialog/dialog.js b/devtools/client/shared/sourceeditor/codemirror/addon/dialog/dialog.js
new file mode 100644
index 0000000000..da1daa7327
--- /dev/null
+++ b/devtools/client/shared/sourceeditor/codemirror/addon/dialog/dialog.js
@@ -0,0 +1,161 @@
+// CodeMirror, copyright (c) by Marijn Haverbeke and others
+// Distributed under an MIT license: https://codemirror.net/LICENSE
+
+// Open simple dialogs on top of an editor. Relies on dialog.css.
+
+(function(mod) {
+  if (typeof exports == "object" && typeof module == "object") // CommonJS
+    mod(require("devtools/client/shared/sourceeditor/codemirror/lib/codemirror"));
+  else if (typeof define == "function" && define.amd) // AMD
+    define(["../../lib/codemirror"], mod);
+  else // Plain browser env
+    mod(CodeMirror);
+})(function(CodeMirror) {
+  function dialogDiv(cm, template, bottom) {
+    var wrap = cm.getWrapperElement();
+    var dialog;
+    dialog = wrap.appendChild(document.createElement("div"));
+    if (bottom)
+      dialog.className = "CodeMirror-dialog CodeMirror-dialog-bottom";
+    else
+      dialog.className = "CodeMirror-dialog CodeMirror-dialog-top";
+
+    if (typeof template == "string") {
+      dialog.innerHTML = template;
+    } else { // Assuming it's a detached DOM element.
+      dialog.appendChild(template);
+    }
+    CodeMirror.addClass(wrap, 'dialog-opened');
+    return dialog;
+  }
+
+  function closeNotification(cm, newVal) {
+    if (cm.state.currentNotificationClose)
+      cm.state.currentNotificationClose();
+    cm.state.currentNotificationClose = newVal;
+  }
+
+  CodeMirror.defineExtension("openDialog", function(template, callback, options) {
+    if (!options) options = {};
+
+    closeNotification(this, null);
+
+    var dialog = dialogDiv(this, template, options.bottom);
+    var closed = false, me = this;
+    function close(newVal) {
+      if (typeof newVal == 'string') {
+        inp.value = newVal;
+      } else {
+        if (closed) return;
+        closed = true;
+        CodeMirror.rmClass(dialog.parentNode, 'dialog-opened');
+        dialog.parentNode.removeChild(dialog);
+        me.focus();
+
+        if (options.onClose) options.onClose(dialog);
+      }
+    }
+
+    var inp = dialog.getElementsByTagName("input")[0], button;
+    if (inp) {
+      inp.focus();
+
+      if (options.value) {
+        inp.value = options.value;
+        if (options.selectValueOnOpen !== false) {
+          inp.select();
+        }
+      }
+
+      if (options.onInput)
+        CodeMirror.on(inp, "input", function(e) { options.onInput(e, inp.value, close);});
+      if (options.onKeyUp)
+        CodeMirror.on(inp, "keyup", function(e) {options.onKeyUp(e, inp.value, close);});
+
+      CodeMirror.on(inp, "keydown", function(e) {
+        if (options && options.onKeyDown && options.onKeyDown(e, inp.value, close)) { return; }
+        if (e.keyCode == 27 || (options.closeOnEnter !== false && e.keyCode == 13)) {
+          inp.blur();
+          CodeMirror.e_stop(e);
+          close();
+        }
+        if (e.keyCode == 13) callback(inp.value, e);
+      });
+
+      if (options.closeOnBlur !== false) CodeMirror.on(inp, "blur", close);
+    } else if (button = dialog.getElementsByTagName("button")[0]) {
+      CodeMirror.on(button, "click", function() {
+        close();
+        me.focus();
+      });
+
+      if (options.closeOnBlur !== false) CodeMirror.on(button, "blur", close);
+
+      button.focus();
+    }
+    return close;
+  });
+
+  CodeMirror.defineExtension("openConfirm", function(template, callbacks, options) {
+    closeNotification(this, null);
+    var dialog = dialogDiv(this, template, options && options.bottom);
+    var buttons = dialog.getElementsByTagName("button");
+    var closed = false, me = this, blurring = 1;
+    function close() {
+      if (closed) return;
+      closed = true;
+      CodeMirror.rmClass(dialog.parentNode, 'dialog-opened');
+      dialog.parentNode.removeChild(dialog);
+      me.focus();
+    }
+    buttons[0].focus();
+    for (var i = 0; i < buttons.length; ++i) {
+      var b = buttons[i];
+      (function(callback) {
+        CodeMirror.on(b, "click", function(e) {
+          CodeMirror.e_preventDefault(e);
+          close();
+          if (callback) callback(me);
+        });
+      })(callbacks[i]);
+      CodeMirror.on(b, "blur", function() {
+        --blurring;
+        setTimeout(function() { if (blurring <= 0) close(); }, 200);
+      });
+      CodeMirror.on(b, "focus", function() { ++blurring; });
+    }
+  });
+
+  /*
+   * openNotification
+   * Opens a notification, that can be closed with an optional timer
+   * (default 5000ms timer) and always closes on click.
+   *
+   * If a notification is opened while another is opened, it will close the
+   * currently opened one and open the new one immediately.
+   */
+  CodeMirror.defineExtension("openNotification", function(template, options) {
+    closeNotification(this, close);
+    var dialog = dialogDiv(this, template, options && options.bottom);
+    var closed = false, doneTimer;
+    var duration = options && typeof options.duration !== "undefined" ? options.duration : 5000;
+
+    function close() {
+      if (closed) return;
+      closed = true;
+      clearTimeout(doneTimer);
+      CodeMirror.rmClass(dialog.parentNode, 'dialog-opened');
+      dialog.parentNode.removeChild(dialog);
+    }
+
+    CodeMirror.on(dialog, 'click', function(e) {
+      CodeMirror.e_preventDefault(e);
+      close();
+    });
+
+    if (duration)
+      doneTimer = setTimeout(close, duration);
+
+    return close;
+  });
+});
diff --git a/devtools/client/shared/sourceeditor/codemirror/addon/display/placeholder.js b/devtools/client/shared/sourceeditor/codemirror/addon/display/placeholder.js
new file mode 100644
index 0000000000..e3f95a49c4
--- /dev/null
+++ b/devtools/client/shared/sourceeditor/codemirror/addon/display/placeholder.js
@@ -0,0 +1,63 @@
+// CodeMirror, copyright (c) by Marijn Haverbeke and others
+// Distributed under an MIT license: https://codemirror.net/LICENSE
+
+(function(mod) {
+  if (typeof exports == "object" && typeof module == "object") // CommonJS
+    mod(require("../../lib/codemirror"));
+  else if (typeof define == "function" && define.amd) // AMD
+    define(["../../lib/codemirror"], mod);
+  else // Plain browser env
+    mod(CodeMirror);
+})(function(CodeMirror) {
+  CodeMirror.defineOption("placeholder", "", function(cm, val, old) {
+    var prev = old && old != CodeMirror.Init;
+    if (val && !prev) {
+      cm.on("blur", onBlur);
+      cm.on("change", onChange);
+      cm.on("swapDoc", onChange);
+      onChange(cm);
+    } else if (!val && prev) {
+      cm.off("blur", onBlur);
+      cm.off("change", onChange);
+      cm.off("swapDoc", onChange);
+      clearPlaceholder(cm);
+      var wrapper = cm.getWrapperElement();
+      wrapper.className = wrapper.className.replace(" CodeMirror-empty", "");
+    }
+
+    if (val && !cm.hasFocus()) onBlur(cm);
+  });
+
+  function clearPlaceholder(cm) {
+    if (cm.state.placeholder) {
+      cm.state.placeholder.parentNode.removeChild(cm.state.placeholder);
+      cm.state.placeholder = null;
+    }
+  }
+  function setPlaceholder(cm) {
+    clearPlaceholder(cm);
+    var elt = cm.state.placeholder = document.createElement("pre");
+    elt.style.cssText = "height: 0; overflow: visible";
+    elt.style.direction = cm.getOption("direction");
+    elt.className = "CodeMirror-placeholder CodeMirror-line-like";
+    var placeHolder = cm.getOption("placeholder")
+    if (typeof placeHolder == "string") placeHolder = document.createTextNode(placeHolder)
+    elt.appendChild(placeHolder)
+    cm.display.lineSpace.insertBefore(elt, cm.display.lineSpace.firstChild);
+  }
+
+  function onBlur(cm) {
+    if (isEmpty(cm)) setPlaceholder(cm);
+  }
+  function onChange(cm) {
+    var wrapper = cm.getWrapperElement(), empty = isEmpty(cm);
+    wrapper.className = wrapper.className.replace(" CodeMirror-empty", "") + (empty ? " CodeMirror-empty" : "");
+
+    if (empty) setPlaceholder(cm);
+    else clearPlaceholder(cm);
+  }
+
+  function isEmpty(cm) {
+    return (cm.lineCount() === 1) && (cm.getLine(0) === "");
+  }
+});
\ No newline at end of file
diff --git a/devtools/client/shared/sourceeditor/codemirror/addon/edit/closebrackets.js b/devtools/client/shared/sourceeditor/codemirror/addon/edit/closebrackets.js
new file mode 100644
index 0000000000..6407d77293
--- /dev/null
+++ b/devtools/client/shared/sourceeditor/codemirror/addon/edit/closebrackets.js
@@ -0,0 +1,191 @@
+// CodeMirror, copyright (c) by Marijn Haverbeke and others
+// Distributed under an MIT license: https://codemirror.net/LICENSE
+
+(function(mod) {
+  if (typeof exports == "object" && typeof module == "object") // CommonJS
+    mod(require("devtools/client/shared/sourceeditor/codemirror/lib/codemirror"));
+  else if (typeof define == "function" && define.amd) // AMD
+    define(["../../lib/codemirror"], mod);
+  else // Plain browser env
+    mod(CodeMirror);
+})(function(CodeMirror) {
+  var defaults = {
+    pairs: "()[]{}''\"\"",
+    closeBefore: ")]}'\":;>",
+    triples: "",
+    explode: "[]{}"
+  };
+
+  var Pos = CodeMirror.Pos;
+
+  CodeMirror.defineOption("autoCloseBrackets", false, function(cm, val, old) {
+    if (old && old != CodeMirror.Init) {
+      cm.removeKeyMap(keyMap);
+      cm.state.closeBrackets = null;
+    }
+    if (val) {
+      ensureBound(getOption(val, "pairs"))
+      cm.state.closeBrackets = val;
+      cm.addKeyMap(keyMap);
+    }
+  });
+
+  function getOption(conf, name) {
+    if (name == "pairs" && typeof conf == "string") return conf;
+    if (typeof conf == "object" && conf[name] != null) return conf[name];
+    return defaults[name];
+  }
+
+  var keyMap = {Backspace: handleBackspace, Enter: handleEnter};
+  function ensureBound(chars) {
+    for (var i = 0; i < chars.length; i++) {
+      var ch = chars.charAt(i), key = "'" + ch + "'"
+      if (!keyMap[key]) keyMap[key] = handler(ch)
+    }
+  }
+  ensureBound(defaults.pairs + "`")
+
+  function handler(ch) {
+    return function(cm) { return handleChar(cm, ch); };
+  }
+
+  function getConfig(cm) {
+    var deflt = cm.state.closeBrackets;
+    if (!deflt || deflt.override) return deflt;
+    var mode = cm.getModeAt(cm.getCursor());
+    return mode.closeBrackets || deflt;
+  }
+
+  function handleBackspace(cm) {
+    var conf = getConfig(cm);
+    if (!conf || cm.getOption("disableInput")) return CodeMirror.Pass;
+
+    var pairs = getOption(conf, "pairs");
+    var ranges = cm.listSelections();
+    for (var i = 0; i < ranges.length; i++) {
+      if (!ranges[i].empty()) return CodeMirror.Pass;
+      var around = charsAround(cm, ranges[i].head);
+      if (!around || pairs.indexOf(around) % 2 != 0) return CodeMirror.Pass;
+    }
+    for (var i = ranges.length - 1; i >= 0; i--) {
+      var cur = ranges[i].head;
+      cm.replaceRange("", Pos(cur.line, cur.ch - 1), Pos(cur.line, cur.ch + 1), "+delete");
+    }
+  }
+
+  function handleEnter(cm) {
+    var conf = getConfig(cm);
+    var explode = conf && getOption(conf, "explode");
+    if (!explode || cm.getOption("disableInput")) return CodeMirror.Pass;
+
+    var ranges = cm.listSelections();
+    for (var i = 0; i < ranges.length; i++) {
+      if (!ranges[i].empty()) return CodeMirror.Pass;
+      var around = charsAround(cm, ranges[i].head);
+      if (!around || explode.indexOf(around) % 2 != 0) return CodeMirror.Pass;
+    }
+    cm.operation(function() {
+      var linesep = cm.lineSeparator() || "\n";
+      cm.replaceSelection(linesep + linesep, null);
+      cm.execCommand("goCharLeft");
+      ranges = cm.listSelections();
+      for (var i = 0; i < ranges.length; i++) {
+        var line = ranges[i].head.line;
+        cm.indentLine(line, null, true);
+        cm.indentLine(line + 1, null, true);
+      }
+    });
+  }
+
+  function contractSelection(sel) {
+    var inverted = CodeMirror.cmpPos(sel.anchor, sel.head) > 0;
+    return {anchor: new Pos(sel.anchor.line, sel.anchor.ch + (inverted ? -1 : 1)),
+            head: new Pos(sel.head.line, sel.head.ch + (inverted ? 1 : -1))};
+  }
+
+  function handleChar(cm, ch) {
+    var conf = getConfig(cm);
+    if (!conf || cm.getOption("disableInput")) return CodeMirror.Pass;
+
+    var pairs = getOption(conf, "pairs");
+    var pos = pairs.indexOf(ch);
+    if (pos == -1) return CodeMirror.Pass;
+
+    var closeBefore = getOption(conf,"closeBefore");
+
+    var triples = getOption(conf, "triples");
+
+    var identical = pairs.charAt(pos + 1) == ch;
+    var ranges = cm.listSelections();
+    var opening = pos % 2 == 0;
+
+    var type;
+    for (var i = 0; i < ranges.length; i++) {
+      var range = ranges[i], cur = range.head, curType;
+      var next = cm.getRange(cur, Pos(cur.line, cur.ch + 1));
+      if (opening && !range.empty()) {
+        curType = "surround";
+      } else if ((identical || !opening) && next == ch) {
+        if (identical && stringStartsAfter(cm, cur))
+          curType = "both";
+        else if (triples.indexOf(ch) >= 0 && cm.getRange(cur, Pos(cur.line, cur.ch + 3)) == ch + ch + ch)
+          curType = "skipThree";
+        else
+          curType = "skip";
+      } else if (identical && cur.ch > 1 && triples.indexOf(ch) >= 0 &&
+                 cm.getRange(Pos(cur.line, cur.ch - 2), cur) == ch + ch) {
+        if (cur.ch > 2 && /\bstring/.test(cm.getTokenTypeAt(Pos(cur.line, cur.ch - 2)))) return CodeMirror.Pass;
+        curType = "addFour";
+      } else if (identical) {
+        var prev = cur.ch == 0 ? " " : cm.getRange(Pos(cur.line, cur.ch - 1), cur)
+        if (!CodeMirror.isWordChar(next) && prev != ch && !CodeMirror.isWordChar(prev)) curType = "both";
+        else return CodeMirror.Pass;
+      } else if (opening && (next.length === 0 || /\s/.test(next) || closeBefore.indexOf(next) > -1)) {
+        curType = "both";
+      } else {
+        return CodeMirror.Pass;
+      }
+      if (!type) type = curType;
+      else if (type != curType) return CodeMirror.Pass;
+    }
+
+    var left = pos % 2 ? pairs.charAt(pos - 1) : ch;
+    var right = pos % 2 ? ch : pairs.charAt(pos + 1);
+    cm.operation(function() {
+      if (type == "skip") {
+        cm.execCommand("goCharRight");
+      } else if (type == "skipThree") {
+        for (var i = 0; i < 3; i++)
+          cm.execCommand("goCharRight");
+      } else if (type == "surround") {
+        var sels = cm.getSelections();
+        for (var i = 0; i < sels.length; i++)
+          sels[i] = left + sels[i] + right;
+        cm.replaceSelections(sels, "around");
+        sels = cm.listSelections().slice();
+        for (var i = 0; i < sels.length; i++)
+          sels[i] = contractSelection(sels[i]);
+        cm.setSelections(sels);
+      } else if (type == "both") {
+        cm.replaceSelection(left + right, null);
+        cm.triggerElectric(left + right);
+        cm.execCommand("goCharLeft");
+      } else if (type == "addFour") {
+        cm.replaceSelection(left + left + left + left, "before");
+        cm.execCommand("goCharRight");
+      }
+    });
+  }
+
+  function charsAround(cm, pos) {
+    var str = cm.getRange(Pos(pos.line, pos.ch - 1),
+                          Pos(pos.line, pos.ch + 1));
+    return str.length == 2 ? str : null;
+  }
+
+  function stringStartsAfter(cm, pos) {
+    var token = cm.getTokenAt(Pos(pos.line, pos.ch + 1))
+    return /\bstring/.test(token.type) && token.start == pos.ch &&
+      (pos.ch == 0 || !/\bstring/.test(cm.getTokenTypeAt(pos)))
+  }
+});
diff --git a/devtools/client/shared/sourceeditor/codemirror/addon/edit/closetag.js b/devtools/client/shared/sourceeditor/codemirror/addon/edit/closetag.js
new file mode 100644
index 0000000000..a5ac43c6fd
--- /dev/null
+++ b/devtools/client/shared/sourceeditor/codemirror/addon/edit/closetag.js
@@ -0,0 +1,184 @@
+// CodeMirror, copyright (c) by Marijn Haverbeke and others
+// Distributed under an MIT license: https://codemirror.net/LICENSE
+
+/**
+ * Tag-closer extension for CodeMirror.
+ *
+ * This extension adds an "autoCloseTags" option that can be set to
+ * either true to get the default behavior, or an object to further
+ * configure its behavior.
+ *
+ * These are supported options:
+ *
+ * `whenClosing` (default true)
+ *   Whether to autoclose when the '/' of a closing tag is typed.
+ * `whenOpening` (default true)
+ *   Whether to autoclose the tag when the final '>' of an opening
+ *   tag is typed.
+ * `dontCloseTags` (default is empty tags for HTML, none for XML)
+ *   An array of tag names that should not be autoclosed.
+ * `indentTags` (default is block tags for HTML, none for XML)
+ *   An array of tag names that should, when opened, cause a
+ *   blank line to be added inside the tag, and the blank line and
+ *   closing line to be indented.
+ * `emptyTags` (default is none)
+ *   An array of XML tag names that should be autoclosed with '/>'.
+ *
+ * See demos/closetag.html for a usage example.
+ */
+
+(function(mod) {
+  if (typeof exports == "object" && typeof module == "object") // CommonJS
+    mod(require("devtools/client/shared/sourceeditor/codemirror/lib/codemirror"), require("devtools/client/shared/sourceeditor/codemirror/addon/fold/xml-fold"));
+  else if (typeof define == "function" && define.amd) // AMD
+    define(["../../lib/codemirror", "../fold/xml-fold"], mod);
+  else // Plain browser env
+    mod(CodeMirror);
+})(function(CodeMirror) {
+  CodeMirror.defineOption("autoCloseTags", false, function(cm, val, old) {
+    if (old != CodeMirror.Init && old)
+      cm.removeKeyMap("autoCloseTags");
+    if (!val) return;
+    var map = {name: "autoCloseTags"};
+    if (typeof val != "object" || val.whenClosing)
+      map["'/'"] = function(cm) { return autoCloseSlash(cm); };
+    if (typeof val != "object" || val.whenOpening)
+      map["'>'"] = function(cm) { return autoCloseGT(cm); };
+    cm.addKeyMap(map);
+  });
+
+  var htmlDontClose = ["area", "base", "br", "col", "command", "embed", "hr", "img", "input", "keygen", "link", "meta", "param",
+                       "source", "track", "wbr"];
+  var htmlIndent = ["applet", "blockquote", "body", "button", "div", "dl", "fieldset", "form", "frameset", "h1", "h2", "h3", "h4",
+                    "h5", "h6", "head", "html", "iframe", "layer", "legend", "object", "ol", "p", "select", "table", "ul"];
+
+  function autoCloseGT(cm) {
+    if (cm.getOption("disableInput")) return CodeMirror.Pass;
+    var ranges = cm.listSelections(), replacements = [];
+    var opt = cm.getOption("autoCloseTags");
+    for (var i = 0; i < ranges.length; i++) {
+      if (!ranges[i].empty()) return CodeMirror.Pass;
+      var pos = ranges[i].head, tok = cm.getTokenAt(pos);
+      var inner = CodeMirror.innerMode(cm.getMode(), tok.state), state = inner.state;
+      var tagInfo = inner.mode.xmlCurrentTag && inner.mode.xmlCurrentTag(state)
+      var tagName = tagInfo && tagInfo.name
+      if (!tagName) return CodeMirror.Pass
+
+      var html = inner.mode.configuration == "html";
+      var dontCloseTags = (typeof opt == "object" && opt.dontCloseTags) || (html && htmlDontClose);
+      var indentTags = (typeof opt == "object" && opt.indentTags) || (html && htmlIndent);
+
+      if (tok.end > pos.ch) tagName = tagName.slice(0, tagName.length - tok.end + pos.ch);
+      var lowerTagName = tagName.toLowerCase();
+      // Don't process the '>' at the end of an end-tag or self-closing tag
+      if (!tagName ||
+          tok.type == "string" && (tok.end != pos.ch || !/[\"\']/.test(tok.string.charAt(tok.string.length - 1)) || tok.string.length == 1) ||
+          tok.type == "tag" && tagInfo.close ||
+          tok.string.indexOf("/") == (tok.string.length - 1) || // match something like <someTagName />
+          dontCloseTags && indexOf(dontCloseTags, lowerTagName) > -1 ||
+          closingTagExists(cm, inner.mode.xmlCurrentContext && inner.mode.xmlCurrentContext(state) || [], tagName, pos, true))
+        return CodeMirror.Pass;
+
+      var emptyTags = typeof opt == "object" && opt.emptyTags;
+      if (emptyTags && indexOf(emptyTags, tagName) > -1) {
+        replacements[i] = { text: "/>", newPos: CodeMirror.Pos(pos.line, pos.ch + 2) };
+        continue;
+      }
+
+      var indent = indentTags && indexOf(indentTags, lowerTagName) > -1;
+      replacements[i] = {indent: indent,
+                         text: ">" + (indent ? "\n\n" : "") + "</" + tagName + ">",
+                         newPos: indent ? CodeMirror.Pos(pos.line + 1, 0) : CodeMirror.Pos(pos.line, pos.ch + 1)};
+    }
+
+    var dontIndentOnAutoClose = (typeof opt == "object" && opt.dontIndentOnAutoClose);
+    for (var i = ranges.length - 1; i >= 0; i--) {
+      var info = replacements[i];
+      cm.replaceRange(info.text, ranges[i].head, ranges[i].anchor, "+insert");
+      var sel = cm.listSelections().slice(0);
+      sel[i] = {head: info.newPos, anchor: info.newPos};
+      cm.setSelections(sel);
+      if (!dontIndentOnAutoClose && info.indent) {
+        cm.indentLine(info.newPos.line, null, true);
+        cm.indentLine(info.newPos.line + 1, null, true);
+      }
+    }
+  }
+
+  function autoCloseCurrent(cm, typingSlash) {
+    var ranges = cm.listSelections(), replacements = [];
+    var head = typingSlash ? "/" : "</";
+    var opt = cm.getOption("autoCloseTags");
+    var dontIndentOnAutoClose = (typeof opt == "object" && opt.dontIndentOnSlash);
+    for (var i = 0; i < ranges.length; i++) {
+      if (!ranges[i].empty()) return CodeMirror.Pass;
+      var pos = ranges[i].head, tok = cm.getTokenAt(pos);
+      var inner = CodeMirror.innerMode(cm.getMode(), tok.state), state = inner.state;
+      if (typingSlash && (tok.type == "string" || tok.string.charAt(0) != "<" ||
+                          tok.start != pos.ch - 1))
+        return CodeMirror.Pass;
+      // Kludge to get around the fact that we are not in XML mode
+      // when completing in JS/CSS snippet in htmlmixed mode. Does not
+      // work for other XML embedded languages (there is no general
+      // way to go from a mixed mode to its current XML state).
+      var replacement, mixed = inner.mode.name != "xml" && cm.getMode().name == "htmlmixed"
+      if (mixed && inner.mode.name == "javascript") {
+        replacement = head + "script";
+      } else if (mixed && inner.mode.name == "css") {
+        replacement = head + "style";
+      } else {
+        var context = inner.mode.xmlCurrentContext && inner.mode.xmlCurrentContext(state)
+        if (!context || (context.length && closingTagExists(cm, context, context[context.length - 1], pos)))
+          return CodeMirror.Pass;
+        replacement = head + context[context.length - 1]
+      }
+      if (cm.getLine(pos.line).charAt(tok.end) != ">") replacement += ">";
+      replacements[i] = replacement;
+    }
+    cm.replaceSelections(replacements);
+    ranges = cm.listSelections();
+    if (!dontIndentOnAutoClose) {
+        for (var i = 0; i < ranges.length; i++)
+            if (i == ranges.length - 1 || ranges[i].head.line < ranges[i + 1].head.line)
+                cm.indentLine(ranges[i].head.line);
+    }
+  }
+
+  function autoCloseSlash(cm) {
+    if (cm.getOption("disableInput")) return CodeMirror.Pass;
+    return autoCloseCurrent(cm, true);
+  }
+
+  CodeMirror.commands.closeTag = function(cm) { return autoCloseCurrent(cm); };
+
+  function indexOf(collection, elt) {
+    if (collection.indexOf) return collection.indexOf(elt);
+    for (var i = 0, e = collection.length; i < e; ++i)
+      if (collection[i] == elt) return i;
+    return -1;
+  }
+
+  // If xml-fold is loaded, we use its functionality to try and verify
+  // whether a given tag is actually unclosed.
+  function closingTagExists(cm, context, tagName, pos, newTag) {
+    if (!CodeMirror.scanForClosingTag) return false;
+    var end = Math.min(cm.lastLine() + 1, pos.line + 500);
+    var nextClose = CodeMirror.scanForClosingTag(cm, pos, null, end);
+    if (!nextClose || nextClose.tag != tagName) return false;
+    // If the immediate wrapping context contains onCx instances of
+    // the same tag, a closing tag only exists if there are at least
+    // that many closing tags of that type following.
+    var onCx = newTag ? 1 : 0
+    for (var i = context.length - 1; i >= 0; i--) {
+      if (context[i] == tagName) ++onCx
+      else break
+    }
+    pos = nextClose.to;
+    for (var i = 1; i < onCx; i++) {
+      var next = CodeMirror.scanForClosingTag(cm, pos, null, end);
+      if (!next || next.tag != tagName) return false;
+      pos = next.to;
+    }
+    return true;
+  }
+});
diff --git a/devtools/client/shared/sourceeditor/codemirror/addon/edit/continuelist.js b/devtools/client/shared/sourceeditor/codemirror/addon/edit/continuelist.js
new file mode 100644
index 0000000000..141d7c826c
--- /dev/null
+++ b/devtools/client/shared/sourceeditor/codemirror/addon/edit/continuelist.js
@@ -0,0 +1,99 @@
+// CodeMirror, copyright (c) by Marijn Haverbeke and others
+// Distributed under an MIT license: https://codemirror.net/LICENSE
+
+(function(mod) {
+  if (typeof exports == "object" && typeof module == "object") // CommonJS
+    mod(require("devtools/client/shared/sourceeditor/codemirror/lib/codemirror"));
+  else if (typeof define == "function" && define.amd) // AMD
+    define(["../../lib/codemirror"], mod);
+  else // Plain browser env
+    mod(CodeMirror);
+})(function(CodeMirror) {
+  "use strict";
+
+  var listRE = /^(\s*)(>[> ]*|[*+-] \[[x ]\]\s|[*+-]\s|(\d+)([.)]))(\s*)/,
+      emptyListRE = /^(\s*)(>[> ]*|[*+-] \[[x ]\]|[*+-]|(\d+)[.)])(\s*)$/,
+      unorderedListRE = /[*+-]\s/;
+
+  CodeMirror.commands.newlineAndIndentContinueMarkdownList = function(cm) {
+    if (cm.getOption("disableInput")) return CodeMirror.Pass;
+    var ranges = cm.listSelections(), replacements = [];
+    for (var i = 0; i < ranges.length; i++) {
+      var pos = ranges[i].head;
+
+      // If we're not in Markdown mode, fall back to normal newlineAndIndent
+      var eolState = cm.getStateAfter(pos.line);
+      var inner = CodeMirror.innerMode(cm.getMode(), eolState);
+      if (inner.mode.name !== "markdown") {
+        cm.execCommand("newlineAndIndent");
+        return;
+      } else {
+        eolState = inner.state;
+      }
+
+      var inList = eolState.list !== false;
+      var inQuote = eolState.quote !== 0;
+
+      var line = cm.getLine(pos.line), match = listRE.exec(line);
+      var cursorBeforeBullet = /^\s*$/.test(line.slice(0, pos.ch));
+      if (!ranges[i].empty() || (!inList && !inQuote) || !match || cursorBeforeBullet) {
+        cm.execCommand("newlineAndIndent");
+        return;
+      }
+      if (emptyListRE.test(line)) {
+        if (!/>\s*$/.test(line)) cm.replaceRange("", {
+          line: pos.line, ch: 0
+        }, {
+          line: pos.line, ch: pos.ch + 1
+        });
+        replacements[i] = "\n";
+      } else {
+        var indent = match[1], after = match[5];
+        var numbered = !(unorderedListRE.test(match[2]) || match[2].indexOf(">") >= 0);
+        var bullet = numbered ? (parseInt(match[3], 10) + 1) + match[4] : match[2].replace("x", " ");
+        replacements[i] = "\n" + indent + bullet + after;
+
+        if (numbered) incrementRemainingMarkdownListNumbers(cm, pos);
+      }
+    }
+
+    cm.replaceSelections(replacements);
+  };
+
+  // Auto-updating Markdown list numbers when a new item is added to the
+  // middle of a list
+  function incrementRemainingMarkdownListNumbers(cm, pos) {
+    var startLine = pos.line, lookAhead = 0, skipCount = 0;
+    var startItem = listRE.exec(cm.getLine(startLine)), startIndent = startItem[1];
+
+    do {
+      lookAhead += 1;
+      var nextLineNumber = startLine + lookAhead;
+      var nextLine = cm.getLine(nextLineNumber), nextItem = listRE.exec(nextLine);
+
+      if (nextItem) {
+        var nextIndent = nextItem[1];
+        var newNumber = (parseInt(startItem[3], 10) + lookAhead - skipCount);
+        var nextNumber = (parseInt(nextItem[3], 10)), itemNumber = nextNumber;
+
+        if (startIndent === nextIndent && !isNaN(nextNumber)) {
+          if (newNumber === nextNumber) itemNumber = nextNumber + 1;
+          if (newNumber > nextNumber) itemNumber = newNumber + 1;
+          cm.replaceRange(
+            nextLine.replace(listRE, nextIndent + itemNumber + nextItem[4] + nextItem[5]),
+          {
+            line: nextLineNumber, ch: 0
+          }, {
+            line: nextLineNumber, ch: nextLine.length
+          });
+        } else {
+          if (startIndent.length > nextIndent.length) return;
+          // This doesn't run if the next line immediatley indents, as it is
+          // not clear of the users intention (new indented item or same level)
+          if ((startIndent.length < nextIndent.length) && (lookAhead === 1)) return;
+          skipCount += 1;
+        }
+      }
+    } while (nextItem);
+  }
+});
diff --git a/devtools/client/shared/sourceeditor/codemirror/addon/edit/matchbrackets.js b/devtools/client/shared/sourceeditor/codemirror/addon/edit/matchbrackets.js
new file mode 100644
index 0000000000..679aafe4a9
--- /dev/null
+++ b/devtools/client/shared/sourceeditor/codemirror/addon/edit/matchbrackets.js
@@ -0,0 +1,150 @@
+// CodeMirror, copyright (c) by Marijn Haverbeke and others
+// Distributed under an MIT license: https://codemirror.net/LICENSE
+
+(function(mod) {
+  if (typeof exports == "object" && typeof module == "object") // CommonJS
+    mod(require("devtools/client/shared/sourceeditor/codemirror/lib/codemirror"));
+  else if (typeof define == "function" && define.amd) // AMD
+    define(["../../lib/codemirror"], mod);
+  else // Plain browser env
+    mod(CodeMirror);
+})(function(CodeMirror) {
+  var ie_lt8 = /MSIE \d/.test(navigator.userAgent) &&
+    (document.documentMode == null || document.documentMode < 8);
+
+  var Pos = CodeMirror.Pos;
+
+  var matching = {"(": ")>", ")": "(<", "[": "]>", "]": "[<", "{": "}>", "}": "{<", "<": ">>", ">": "<<"};
+
+  function bracketRegex(config) {
+    return config && config.bracketRegex || /[(){}[\]]/
+  }
+
+  function findMatchingBracket(cm, where, config) {
+    var line = cm.getLineHandle(where.line), pos = where.ch - 1;
+    var afterCursor = config && config.afterCursor
+    if (afterCursor == null)
+      afterCursor = /(^| )cm-fat-cursor($| )/.test(cm.getWrapperElement().className)
+    var re = bracketRegex(config)
+
+    // A cursor is defined as between two characters, but in in vim command mode
+    // (i.e. not insert mode), the cursor is visually represented as a
+    // highlighted box on top of the 2nd character. Otherwise, we allow matches
+    // from before or after the cursor.
+    var match = (!afterCursor && pos >= 0 && re.test(line.text.charAt(pos)) && matching[line.text.charAt(pos)]) ||
+        re.test(line.text.charAt(pos + 1)) && matching[line.text.charAt(++pos)];
+    if (!match) return null;
+    var dir = match.charAt(1) == ">" ? 1 : -1;
+    if (config && config.strict && (dir > 0) != (pos == where.ch)) return null;
+    var style = cm.getTokenTypeAt(Pos(where.line, pos + 1));
+
+    var found = scanForBracket(cm, Pos(where.line, pos + (dir > 0 ? 1 : 0)), dir, style || null, config);
+    if (found == null) return null;
+    return {from: Pos(where.line, pos), to: found && found.pos,
+            match: found && found.ch == match.charAt(0), forward: dir > 0};
+  }
+
+  // bracketRegex is used to specify which type of bracket to scan
+  // should be a regexp, e.g. /[[\]]/
+  //
+  // Note: If "where" is on an open bracket, then this bracket is ignored.
+  //
+  // Returns false when no bracket was found, null when it reached
+  // maxScanLines and gave up
+  function scanForBracket(cm, where, dir, style, config) {
+    var maxScanLen = (config && config.maxScanLineLength) || 10000;
+    var maxScanLines = (config && config.maxScanLines) || 1000;
+
+    var stack = [];
+    var re = bracketRegex(config)
+    var lineEnd = dir > 0 ? Math.min(where.line + maxScanLines, cm.lastLine() + 1)
+                          : Math.max(cm.firstLine() - 1, where.line - maxScanLines);
+    for (var lineNo = where.line; lineNo != lineEnd; lineNo += dir) {
+      var line = cm.getLine(lineNo);
+      if (!line) continue;
+      var pos = dir > 0 ? 0 : line.length - 1, end = dir > 0 ? line.length : -1;
+      if (line.length > maxScanLen) continue;
+      if (lineNo == where.line) pos = where.ch - (dir < 0 ? 1 : 0);
+      for (; pos != end; pos += dir) {
+        var ch = line.charAt(pos);
+        if (re.test(ch) && (style === undefined || cm.getTokenTypeAt(Pos(lineNo, pos + 1)) == style)) {
+          var match = matching[ch];
+          if (match && (match.charAt(1) == ">") == (dir > 0)) stack.push(ch);
+          else if (!stack.length) return {pos: Pos(lineNo, pos), ch: ch};
+          else stack.pop();
+        }
+      }
+    }
+    return lineNo - dir == (dir > 0 ? cm.lastLine() : cm.firstLine()) ? false : null;
+  }
+
+  function matchBrackets(cm, autoclear, config) {
+    // Disable brace matching in long lines, since it'll cause hugely slow updates
+    var maxHighlightLen = cm.state.matchBrackets.maxHighlightLineLength || 1000;
+    var marks = [], ranges = cm.listSelections();
+    for (var i = 0; i < ranges.length; i++) {
+      var match = ranges[i].empty() && findMatchingBracket(cm, ranges[i].head, config);
+      if (match && cm.getLine(match.from.line).length <= maxHighlightLen) {
+        var style = match.match ? "CodeMirror-matchingbracket" : "CodeMirror-nonmatchingbracket";
+        marks.push(cm.markText(match.from, Pos(match.from.line, match.from.ch + 1), {className: style}));
+        if (match.to && cm.getLine(match.to.line).length <= maxHighlightLen)
+          marks.push(cm.markText(match.to, Pos(match.to.line, match.to.ch + 1), {className: style}));
+      }
+    }
+
+    if (marks.length) {
+      // Kludge to work around the IE bug from issue #1193, where text
+      // input stops going to the textare whever this fires.
+      if (ie_lt8 && cm.state.focused) cm.focus();
+
+      var clear = function() {
+        cm.operation(function() {
+          for (var i = 0; i < marks.length; i++) marks[i].clear();
+        });
+      };
+      if (autoclear) setTimeout(clear, 800);
+      else return clear;
+    }
+  }
+
+  function doMatchBrackets(cm) {
+    cm.operation(function() {
+      if (cm.state.matchBrackets.currentlyHighlighted) {
+        cm.state.matchBrackets.currentlyHighlighted();
+        cm.state.matchBrackets.currentlyHighlighted = null;
+      }
+      cm.state.matchBrackets.currentlyHighlighted = matchBrackets(cm, false, cm.state.matchBrackets);
+    });
+  }
+
+  CodeMirror.defineOption("matchBrackets", false, function(cm, val, old) {
+    if (old && old != CodeMirror.Init) {
+      cm.off("cursorActivity", doMatchBrackets);
+      if (cm.state.matchBrackets && cm.state.matchBrackets.currentlyHighlighted) {
+        cm.state.matchBrackets.currentlyHighlighted();
+        cm.state.matchBrackets.currentlyHighlighted = null;
+      }
+    }
+    if (val) {
+      cm.state.matchBrackets = typeof val == "object" ? val : {};
+      cm.on("cursorActivity", doMatchBrackets);
+    }
+  });
+
+  CodeMirror.defineExtension("matchBrackets", function() {matchBrackets(this, true);});
+  CodeMirror.defineExtension("findMatchingBracket", function(pos, config, oldConfig){
+    // Backwards-compatibility kludge
+    if (oldConfig || typeof config == "boolean") {
+      if (!oldConfig) {
+        config = config ? {strict: true} : null
+      } else {
+        oldConfig.strict = config
+        config = oldConfig
+      }
+    }
+    return findMatchingBracket(this, pos, config)
+  });
+  CodeMirror.defineExtension("scanForBracket", function(pos, dir, style, config){
+    return scanForBracket(this, pos, dir, style, config);
+  });
+});
diff --git a/devtools/client/shared/sourceeditor/codemirror/addon/edit/matchtags.js b/devtools/client/shared/sourceeditor/codemirror/addon/edit/matchtags.js
new file mode 100644
index 0000000000..95350f4958
--- /dev/null
+++ b/devtools/client/shared/sourceeditor/codemirror/addon/edit/matchtags.js
@@ -0,0 +1,66 @@
+// CodeMirror, copyright (c) by Marijn Haverbeke and others
+// Distributed under an MIT license: https://codemirror.net/LICENSE
+
+(function(mod) {
+  if (typeof exports == "object" && typeof module == "object") // CommonJS
+    mod(require("devtools/client/shared/sourceeditor/codemirror/lib/codemirror"), require("devtools/client/shared/sourceeditor/codemirror/addon/fold/xml-fold"));
+  else if (typeof define == "function" && define.amd) // AMD
+    define(["../../lib/codemirror", "../fold/xml-fold"], mod);
+  else // Plain browser env
+    mod(CodeMirror);
+})(function(CodeMirror) {
+  "use strict";
+
+  CodeMirror.defineOption("matchTags", false, function(cm, val, old) {
+    if (old && old != CodeMirror.Init) {
+      cm.off("cursorActivity", doMatchTags);
+      cm.off("viewportChange", maybeUpdateMatch);
+      clear(cm);
+    }
+    if (val) {
+      cm.state.matchBothTags = typeof val == "object" && val.bothTags;
+      cm.on("cursorActivity", doMatchTags);
+      cm.on("viewportChange", maybeUpdateMatch);
+      doMatchTags(cm);
+    }
+  });
+
+  function clear(cm) {
+    if (cm.state.tagHit) cm.state.tagHit.clear();
+    if (cm.state.tagOther) cm.state.tagOther.clear();
+    cm.state.tagHit = cm.state.tagOther = null;
+  }
+
+  function doMatchTags(cm) {
+    cm.state.failedTagMatch = false;
+    cm.operation(function() {
+      clear(cm);
+      if (cm.somethingSelected()) return;
+      var cur = cm.getCursor(), range = cm.getViewport();
+      range.from = Math.min(range.from, cur.line); range.to = Math.max(cur.line + 1, range.to);
+      var match = CodeMirror.findMatchingTag(cm, cur, range);
+      if (!match) return;
+      if (cm.state.matchBothTags) {
+        var hit = match.at == "open" ? match.open : match.close;
+        if (hit) cm.state.tagHit = cm.markText(hit.from, hit.to, {className: "CodeMirror-matchingtag"});
+      }
+      var other = match.at == "close" ? match.open : match.close;
+      if (other)
+        cm.state.tagOther = cm.markText(other.from, other.to, {className: "CodeMirror-matchingtag"});
+      else
+        cm.state.failedTagMatch = true;
+    });
+  }
+
+  function maybeUpdateMatch(cm) {
+    if (cm.state.failedTagMatch) doMatchTags(cm);
+  }
+
+  CodeMirror.commands.toMatchingTag = function(cm) {
+    var found = CodeMirror.findMatchingTag(cm, cm.getCursor());
+    if (found) {
+      var other = found.at == "close" ? found.open : found.close;
+      if (other) cm.extendSelection(other.to, other.from);
+    }
+  };
+});
diff --git a/devtools/client/shared/sourceeditor/codemirror/addon/edit/trailingspace.js b/devtools/client/shared/sourceeditor/codemirror/addon/edit/trailingspace.js
new file mode 100644
index 0000000000..293c6e5c20
--- /dev/null
+++ b/devtools/client/shared/sourceeditor/codemirror/addon/edit/trailingspace.js
@@ -0,0 +1,27 @@
+// CodeMirror, copyright (c) by Marijn Haverbeke and others
+// Distributed under an MIT license: https://codemirror.net/LICENSE
+
+(function(mod) {
+  if (typeof exports == "object" && typeof module == "object") // CommonJS
+    mod(require("devtools/client/shared/sourceeditor/codemirror/lib/codemirror"));
+  else if (typeof define == "function" && define.amd) // AMD
+    define(["../../lib/codemirror"], mod);
+  else // Plain browser env
+    mod(CodeMirror);
+})(function(CodeMirror) {
+  CodeMirror.defineOption("showTrailingSpace", false, function(cm, val, prev) {
+    if (prev == CodeMirror.Init) prev = false;
+    if (prev && !val)
+      cm.removeOverlay("trailingspace");
+    else if (!prev && val)
+      cm.addOverlay({
+        token: function(stream) {
+          for (var l = stream.string.length, i = l; i && /\s/.test(stream.string.charAt(i - 1)); --i) {}
+          if (i > stream.pos) { stream.pos = i; return null; }
+          stream.pos = l;
+          return "trailingspace";
+        },
+        name: "trailingspace"
+      });
+  });
+});
diff --git a/devtools/client/shared/sourceeditor/codemirror/addon/fold/brace-fold.js b/devtools/client/shared/sourceeditor/codemirror/addon/fold/brace-fold.js
new file mode 100644
index 0000000000..1d80cee5f1
--- /dev/null
+++ b/devtools/client/shared/sourceeditor/codemirror/addon/fold/brace-fold.js
@@ -0,0 +1,105 @@
+// CodeMirror, copyright (c) by Marijn Haverbeke and others
+// Distributed under an MIT license: https://codemirror.net/LICENSE
+
+(function(mod) {
+  if (typeof exports == "object" && typeof module == "object") // CommonJS
+    mod(require("devtools/client/shared/sourceeditor/codemirror/lib/codemirror"));
+  else if (typeof define == "function" && define.amd) // AMD
+    define(["../../lib/codemirror"], mod);
+  else // Plain browser env
+    mod(CodeMirror);
+})(function(CodeMirror) {
+"use strict";
+
+CodeMirror.registerHelper("fold", "brace", function(cm, start) {
+  var line = start.line, lineText = cm.getLine(line);
+  var tokenType;
+
+  function findOpening(openCh) {
+    for (var at = start.ch, pass = 0;;) {
+      var found = at <= 0 ? -1 : lineText.lastIndexOf(openCh, at - 1);
+      if (found == -1) {
+        if (pass == 1) break;
+        pass = 1;
+        at = lineText.length;
+        continue;
+      }
+      if (pass == 1 && found < start.ch) break;
+      tokenType = cm.getTokenTypeAt(CodeMirror.Pos(line, found + 1));
+      if (!/^(comment|string)/.test(tokenType)) return found + 1;
+      at = found - 1;
+    }
+  }
+
+  var startToken = "{", endToken = "}", startCh = findOpening("{");
+  if (startCh == null) {
+    startToken = "[", endToken = "]";
+    startCh = findOpening("[");
+  }
+
+  if (startCh == null) return;
+  var count = 1, lastLine = cm.lastLine(), end, endCh;
+  outer: for (var i = line; i <= lastLine; ++i) {
+    var text = cm.getLine(i), pos = i == line ? startCh : 0;
+    for (;;) {
+      var nextOpen = text.indexOf(startToken, pos), nextClose = text.indexOf(endToken, pos);
+      if (nextOpen < 0) nextOpen = text.length;
+      if (nextClose < 0) nextClose = text.length;
+      pos = Math.min(nextOpen, nextClose);
+      if (pos == text.length) break;
+      if (cm.getTokenTypeAt(CodeMirror.Pos(i, pos + 1)) == tokenType) {
+        if (pos == nextOpen) ++count;
+        else if (!--count) { end = i; endCh = pos; break outer; }
+      }
+      ++pos;
+    }
+  }
+  if (end == null || line == end) return;
+  return {from: CodeMirror.Pos(line, startCh),
+          to: CodeMirror.Pos(end, endCh)};
+});
+
+CodeMirror.registerHelper("fold", "import", function(cm, start) {
+  function hasImport(line) {
+    if (line < cm.firstLine() || line > cm.lastLine()) return null;
+    var start = cm.getTokenAt(CodeMirror.Pos(line, 1));
+    if (!/\S/.test(start.string)) start = cm.getTokenAt(CodeMirror.Pos(line, start.end + 1));
+    if (start.type != "keyword" || start.string != "import") return null;
+    // Now find closing semicolon, return its position
+    for (var i = line, e = Math.min(cm.lastLine(), line + 10); i <= e; ++i) {
+      var text = cm.getLine(i), semi = text.indexOf(";");
+      if (semi != -1) return {startCh: start.end, end: CodeMirror.Pos(i, semi)};
+    }
+  }
+
+  var startLine = start.line, has = hasImport(startLine), prev;
+  if (!has || hasImport(startLine - 1) || ((prev = hasImport(startLine - 2)) && prev.end.line == startLine - 1))
+    return null;
+  for (var end = has.end;;) {
+    var next = hasImport(end.line + 1);
+    if (next == null) break;
+    end = next.end;
+  }
+  return {from: cm.clipPos(CodeMirror.Pos(startLine, has.startCh + 1)), to: end};
+});
+
+CodeMirror.registerHelper("fold", "include", function(cm, start) {
+  function hasInclude(line) {
+    if (line < cm.firstLine() || line > cm.lastLine()) return null;
+    var start = cm.getTokenAt(CodeMirror.Pos(line, 1));
+    if (!/\S/.test(start.string)) start = cm.getTokenAt(CodeMirror.Pos(line, start.end + 1));
+    if (start.type == "meta" && start.string.slice(0, 8) == "#include") return start.start + 8;
+  }
+
+  var startLine = start.line, has = hasInclude(startLine);
+  if (has == null || hasInclude(startLine - 1) != null) return null;
+  for (var end = startLine;;) {
+    var next = hasInclude(end + 1);
+    if (next == null) break;
+    ++end;
+  }
+  return {from: CodeMirror.Pos(startLine, has + 1),
+          to: cm.clipPos(CodeMirror.Pos(end))};
+});
+
+});
diff --git a/devtools/client/shared/sourceeditor/codemirror/addon/fold/comment-fold.js b/devtools/client/shared/sourceeditor/codemirror/addon/fold/comment-fold.js
new file mode 100644
index 0000000000..6b1bd82869
--- /dev/null
+++ b/devtools/client/shared/sourceeditor/codemirror/addon/fold/comment-fold.js
@@ -0,0 +1,59 @@
+// CodeMirror, copyright (c) by Marijn Haverbeke and others
+// Distributed under an MIT license: https://codemirror.net/LICENSE
+
+(function(mod) {
+  if (typeof exports == "object" && typeof module == "object") // CommonJS
+    mod(require("devtools/client/shared/sourceeditor/codemirror/lib/codemirror"));
+  else if (typeof define == "function" && define.amd) // AMD
+    define(["../../lib/codemirror"], mod);
+  else // Plain browser env
+    mod(CodeMirror);
+})(function(CodeMirror) {
+"use strict";
+
+CodeMirror.registerGlobalHelper("fold", "comment", function(mode) {
+  return mode.blockCommentStart && mode.blockCommentEnd;
+}, function(cm, start) {
+  var mode = cm.getModeAt(start), startToken = mode.blockCommentStart, endToken = mode.blockCommentEnd;
+  if (!startToken || !endToken) return;
+  var line = start.line, lineText = cm.getLine(line);
+
+  var startCh;
+  for (var at = start.ch, pass = 0;;) {
+    var found = at <= 0 ? -1 : lineText.lastIndexOf(startToken, at - 1);
+    if (found == -1) {
+      if (pass == 1) return;
+      pass = 1;
+      at = lineText.length;
+      continue;
+    }
+    if (pass == 1 && found < start.ch) return;
+    if (/comment/.test(cm.getTokenTypeAt(CodeMirror.Pos(line, found + 1))) &&
+        (found == 0 || lineText.slice(found - endToken.length, found) == endToken ||
+         !/comment/.test(cm.getTokenTypeAt(CodeMirror.Pos(line, found))))) {
+      startCh = found + startToken.length;
+      break;
+    }
+    at = found - 1;
+  }
+
+  var depth = 1, lastLine = cm.lastLine(), end, endCh;
+  outer: for (var i = line; i <= lastLine; ++i) {
+    var text = cm.getLine(i), pos = i == line ? startCh : 0;
+    for (;;) {
+      var nextOpen = text.indexOf(startToken, pos), nextClose = text.indexOf(endToken, pos);
+      if (nextOpen < 0) nextOpen = text.length;
+      if (nextClose < 0) nextClose = text.length;
+      pos = Math.min(nextOpen, nextClose);
+      if (pos == text.length) break;
+      if (pos == nextOpen) ++depth;
+      else if (!--depth) { end = i; endCh = pos; break outer; }
+      ++pos;
+    }
+  }
+  if (end == null || line == end && endCh == startCh) return;
+  return {from: CodeMirror.Pos(line, startCh),
+          to: CodeMirror.Pos(end, endCh)};
+});
+
+});
diff --git a/devtools/client/shared/sourceeditor/codemirror/addon/fold/foldcode.js b/devtools/client/shared/sourceeditor/codemirror/addon/fold/foldcode.js
new file mode 100644
index 0000000000..5f55d9d454
--- /dev/null
+++ b/devtools/client/shared/sourceeditor/codemirror/addon/fold/foldcode.js
@@ -0,0 +1,152 @@
+// CodeMirror, copyright (c) by Marijn Haverbeke and others
+// Distributed under an MIT license: https://codemirror.net/LICENSE
+
+(function(mod) {
+  if (typeof exports == "object" && typeof module == "object") // CommonJS
+    mod(require("devtools/client/shared/sourceeditor/codemirror/lib/codemirror"));
+  else if (typeof define == "function" && define.amd) // AMD
+    define(["../../lib/codemirror"], mod);
+  else // Plain browser env
+    mod(CodeMirror);
+})(function(CodeMirror) {
+  "use strict";
+
+  function doFold(cm, pos, options, force) {
+    if (options && options.call) {
+      var finder = options;
+      options = null;
+    } else {
+      var finder = getOption(cm, options, "rangeFinder");
+    }
+    if (typeof pos == "number") pos = CodeMirror.Pos(pos, 0);
+    var minSize = getOption(cm, options, "minFoldSize");
+
+    function getRange(allowFolded) {
+      var range = finder(cm, pos);
+      if (!range || range.to.line - range.from.line < minSize) return null;
+      var marks = cm.findMarksAt(range.from);
+      for (var i = 0; i < marks.length; ++i) {
+        if (marks[i].__isFold && force !== "fold") {
+          if (!allowFolded) return null;
+          range.cleared = true;
+          marks[i].clear();
+        }
+      }
+      return range;
+    }
+
+    var range = getRange(true);
+    if (getOption(cm, options, "scanUp")) while (!range && pos.line > cm.firstLine()) {
+      pos = CodeMirror.Pos(pos.line - 1, 0);
+      range = getRange(false);
+    }
+    if (!range || range.cleared || force === "unfold") return;
+
+    var myWidget = makeWidget(cm, options);
+    CodeMirror.on(myWidget, "mousedown", function(e) {
+      myRange.clear();
+      CodeMirror.e_preventDefault(e);
+    });
+    var myRange = cm.markText(range.from, range.to, {
+      replacedWith: myWidget,
+      clearOnEnter: getOption(cm, options, "clearOnEnter"),
+      __isFold: true
+    });
+    myRange.on("clear", function(from, to) {
+      CodeMirror.signal(cm, "unfold", cm, from, to);
+    });
+    CodeMirror.signal(cm, "fold", cm, range.from, range.to);
+  }
+
+  function makeWidget(cm, options) {
+    var widget = getOption(cm, options, "widget");
+    if (typeof widget == "string") {
+      var text = document.createTextNode(widget);
+      widget = document.createElement("span");
+      widget.appendChild(text);
+      widget.className = "CodeMirror-foldmarker";
+    } else if (widget) {
+      widget = widget.cloneNode(true)
+    }
+    return widget;
+  }
+
+  // Clumsy backwards-compatible interface
+  CodeMirror.newFoldFunction = function(rangeFinder, widget) {
+    return function(cm, pos) { doFold(cm, pos, {rangeFinder: rangeFinder, widget: widget}); };
+  };
+
+  // New-style interface
+  CodeMirror.defineExtension("foldCode", function(pos, options, force) {
+    doFold(this, pos, options, force);
+  });
+
+  CodeMirror.defineExtension("isFolded", function(pos) {
+    var marks = this.findMarksAt(pos);
+    for (var i = 0; i < marks.length; ++i)
+      if (marks[i].__isFold) return true;
+  });
+
+  CodeMirror.commands.toggleFold = function(cm) {
+    cm.foldCode(cm.getCursor());
+  };
+  CodeMirror.commands.fold = function(cm) {
+    cm.foldCode(cm.getCursor(), null, "fold");
+  };
+  CodeMirror.commands.unfold = function(cm) {
+    cm.foldCode(cm.getCursor(), null, "unfold");
+  };
+  CodeMirror.commands.foldAll = function(cm) {
+    cm.operation(function() {
+      for (var i = cm.firstLine(), e = cm.lastLine(); i <= e; i++)
+        cm.foldCode(CodeMirror.Pos(i, 0), null, "fold");
+    });
+  };
+  CodeMirror.commands.unfoldAll = function(cm) {
+    cm.operation(function() {
+      for (var i = cm.firstLine(), e = cm.lastLine(); i <= e; i++)
+        cm.foldCode(CodeMirror.Pos(i, 0), null, "unfold");
+    });
+  };
+
+  CodeMirror.registerHelper("fold", "combine", function() {
+    var funcs = Array.prototype.slice.call(arguments, 0);
+    return function(cm, start) {
+      for (var i = 0; i < funcs.length; ++i) {
+        var found = funcs[i](cm, start);
+        if (found) return found;
+      }
+    };
+  });
+
+  CodeMirror.registerHelper("fold", "auto", function(cm, start) {
+    var helpers = cm.getHelpers(start, "fold");
+    for (var i = 0; i < helpers.length; i++) {
+      var cur = helpers[i](cm, start);
+      if (cur) return cur;
+    }
+  });
+
+  var defaultOptions = {
+    rangeFinder: CodeMirror.fold.auto,
+    widget: "\u2194",
+    minFoldSize: 0,
+    scanUp: false,
+    clearOnEnter: true
+  };
+
+  CodeMirror.defineOption("foldOptions", null);
+
+  function getOption(cm, options, name) {
+    if (options && options[name] !== undefined)
+      return options[name];
+    var editorOptions = cm.options.foldOptions;
+    if (editorOptions && editorOptions[name] !== undefined)
+      return editorOptions[name];
+    return defaultOptions[name];
+  }
+
+  CodeMirror.defineExtension("foldOption", function(options, name) {
+    return getOption(this, options, name);
+  });
+});
diff --git a/devtools/client/shared/sourceeditor/codemirror/addon/fold/foldgutter.css b/devtools/client/shared/sourceeditor/codemirror/addon/fold/foldgutter.css
new file mode 100644
index 0000000000..ad19ae2d3e
--- /dev/null
+++ b/devtools/client/shared/sourceeditor/codemirror/addon/fold/foldgutter.css
@@ -0,0 +1,20 @@
+.CodeMirror-foldmarker {
+  color: blue;
+  text-shadow: #b9f 1px 1px 2px, #b9f -1px -1px 2px, #b9f 1px -1px 2px, #b9f -1px 1px 2px;
+  font-family: arial;
+  line-height: .3;
+  cursor: pointer;
+}
+.CodeMirror-foldgutter {
+  width: .7em;
+}
+.CodeMirror-foldgutter-open,
+.CodeMirror-foldgutter-folded {
+  cursor: pointer;
+}
+.CodeMirror-foldgutter-open:after {
+  content: "\25BE";
+}
+.CodeMirror-foldgutter-folded:after {
+  content: "\25B8";
+}
diff --git a/devtools/client/shared/sourceeditor/codemirror/addon/fold/foldgutter.js b/devtools/client/shared/sourceeditor/codemirror/addon/fold/foldgutter.js
new file mode 100644
index 0000000000..b74a9013f9
--- /dev/null
+++ b/devtools/client/shared/sourceeditor/codemirror/addon/fold/foldgutter.js
@@ -0,0 +1,151 @@
+// CodeMirror, copyright (c) by Marijn Haverbeke and others
+// Distributed under an MIT license: https://codemirror.net/LICENSE
+
+(function(mod) {
+  if (typeof exports == "object" && typeof module == "object") // CommonJS
+    mod(require("devtools/client/shared/sourceeditor/codemirror/lib/codemirror"), require("devtools/client/shared/sourceeditor/codemirror/addon/fold/foldcode"));
+  else if (typeof define == "function" && define.amd) // AMD
+    define(["../../lib/codemirror", "./foldcode"], mod);
+  else // Plain browser env
+    mod(CodeMirror);
+})(function(CodeMirror) {
+  "use strict";
+
+  CodeMirror.defineOption("foldGutter", false, function(cm, val, old) {
+    if (old && old != CodeMirror.Init) {
+      cm.clearGutter(cm.state.foldGutter.options.gutter);
+      cm.state.foldGutter = null;
+      cm.off("gutterClick", onGutterClick);
+      cm.off("changes", onChange);
+      cm.off("viewportChange", onViewportChange);
+      cm.off("fold", onFold);
+      cm.off("unfold", onFold);
+      cm.off("swapDoc", onChange);
+    }
+    if (val) {
+      cm.state.foldGutter = new State(parseOptions(val));
+      updateInViewport(cm);
+      cm.on("gutterClick", onGutterClick);
+      cm.on("changes", onChange);
+      cm.on("viewportChange", onViewportChange);
+      cm.on("fold", onFold);
+      cm.on("unfold", onFold);
+      cm.on("swapDoc", onChange);
+    }
+  });
+
+  var Pos = CodeMirror.Pos;
+
+  function State(options) {
+    this.options = options;
+    this.from = this.to = 0;
+  }
+
+  function parseOptions(opts) {
+    if (opts === true) opts = {};
+    if (opts.gutter == null) opts.gutter = "CodeMirror-foldgutter";
+    if (opts.indicatorOpen == null) opts.indicatorOpen = "CodeMirror-foldgutter-open";
+    if (opts.indicatorFolded == null) opts.indicatorFolded = "CodeMirror-foldgutter-folded";
+    return opts;
+  }
+
+  function isFolded(cm, line) {
+    var marks = cm.findMarks(Pos(line, 0), Pos(line + 1, 0));
+    for (var i = 0; i < marks.length; ++i) {
+      if (marks[i].__isFold) {
+        var fromPos = marks[i].find(-1);
+        if (fromPos && fromPos.line === line)
+          return marks[i];
+      }
+    }
+  }
+
+  function marker(spec) {
+    if (typeof spec == "string") {
+      var elt = document.createElement("div");
+      elt.className = spec + " CodeMirror-guttermarker-subtle";
+      return elt;
+    } else {
+      return spec.cloneNode(true);
+    }
+  }
+
+  function updateFoldInfo(cm, from, to) {
+    var opts = cm.state.foldGutter.options, cur = from;
+    var minSize = cm.foldOption(opts, "minFoldSize");
+    var func = cm.foldOption(opts, "rangeFinder");
+    cm.eachLine(from, to, function(line) {
+      var mark = null;
+      if (isFolded(cm, cur)) {
+        mark = marker(opts.indicatorFolded);
+      } else {
+        var pos = Pos(cur, 0);
+        var range = func && func(cm, pos);
+        if (range && range.to.line - range.from.line >= minSize)
+          mark = marker(opts.indicatorOpen);
+      }
+      cm.setGutterMarker(line, opts.gutter, mark);
+      ++cur;
+    });
+  }
+
+  function updateInViewport(cm) {
+    var vp = cm.getViewport(), state = cm.state.foldGutter;
+    if (!state) return;
+    cm.operation(function() {
+      updateFoldInfo(cm, vp.from, vp.to);
+    });
+    state.from = vp.from; state.to = vp.to;
+  }
+
+  function onGutterClick(cm, line, gutter) {
+    var state = cm.state.foldGutter;
+    if (!state) return;
+    var opts = state.options;
+    if (gutter != opts.gutter) return;
+    var folded = isFolded(cm, line);
+    if (folded) folded.clear();
+    else cm.foldCode(Pos(line, 0), opts);
+  }
+
+  function onChange(cm) {
+    var state = cm.state.foldGutter;
+    if (!state) return;
+    var opts = state.options;
+    state.from = state.to = 0;
+    clearTimeout(state.changeUpdate);
+    state.changeUpdate = setTimeout(function() { updateInViewport(cm); }, opts.foldOnChangeTimeSpan || 600);
+  }
+
+  function onViewportChange(cm) {
+    var state = cm.state.foldGutter;
+    if (!state) return;
+    var opts = state.options;
+    clearTimeout(state.changeUpdate);
+    state.changeUpdate = setTimeout(function() {
+      var vp = cm.getViewport();
+      if (state.from == state.to || vp.from - state.to > 20 || state.from - vp.to > 20) {
+        updateInViewport(cm);
+      } else {
+        cm.operation(function() {
+          if (vp.from < state.from) {
+            updateFoldInfo(cm, vp.from, state.from);
+            state.from = vp.from;
+          }
+          if (vp.to > state.to) {
+            updateFoldInfo(cm, state.to, vp.to);
+            state.to = vp.to;
+          }
+        });
+      }
+    }, opts.updateViewportTimeSpan || 400);
+  }
+
+  function onFold(cm, from) {
+    var state = cm.state.foldGutter;
+    if (!state) return;
+    var line = from.line;
+    if (line >= state.from && line < state.to)
+      updateFoldInfo(cm, line, line + 1);
+  }
+});
diff --git a/devtools/client/shared/sourceeditor/codemirror/addon/fold/indent-fold.js b/devtools/client/shared/sourceeditor/codemirror/addon/fold/indent-fold.js
new file mode 100644
index 0000000000..071de5b3c5
--- /dev/null
+++ b/devtools/client/shared/sourceeditor/codemirror/addon/fold/indent-fold.js
@@ -0,0 +1,48 @@
+// CodeMirror, copyright (c) by Marijn Haverbeke and others
+// Distributed under an MIT license: https://codemirror.net/LICENSE
+
+(function(mod) {
+  if (typeof exports == "object" && typeof module == "object") // CommonJS
+    mod(require("devtools/client/shared/sourceeditor/codemirror/lib/codemirror"));
+  else if (typeof define == "function" && define.amd) // AMD
+    define(["../../lib/codemirror"], mod);
+  else // Plain browser env
+    mod(CodeMirror);
+})(function(CodeMirror) {
+"use strict";
+
+function lineIndent(cm, lineNo) {
+  var text = cm.getLine(lineNo)
+  var spaceTo = text.search(/\S/)
+  if (spaceTo == -1 || /\bcomment\b/.test(cm.getTokenTypeAt(CodeMirror.Pos(lineNo, spaceTo + 1))))
+    return -1
+  return CodeMirror.countColumn(text, null, cm.getOption("tabSize"))
+}
+
+CodeMirror.registerHelper("fold", "indent", function(cm, start) {
+  var myIndent = lineIndent(cm, start.line)
+  if (myIndent < 0) return
+  var lastLineInFold = null
+
+  // Go through lines until we find a line that definitely doesn't belong in
+  // the block we're folding, or to the end.
+  for (var i = start.line + 1, end = cm.lastLine(); i <= end; ++i) {
+    var indent = lineIndent(cm, i)
+    if (indent == -1) {
+    } else if (indent > myIndent) {
+      // Lines with a greater indent are considered part of the block.
+      lastLineInFold = i;
+    } else {
+      // If this line has non-space, non-comment content, and is
+      // indented less or equal to the start line, it is the start of
+      // another block.
+      break;
+    }
+  }
+  if (lastLineInFold) return {
+    from: CodeMirror.Pos(start.line, cm.getLine(start.line).length),
+    to: CodeMirror.Pos(lastLineInFold, cm.getLine(lastLineInFold).length)
+  };
+});
+
+});
diff --git a/devtools/client/shared/sourceeditor/codemirror/addon/fold/markdown-fold.js b/devtools/client/shared/sourceeditor/codemirror/addon/fold/markdown-fold.js
new file mode 100644
index 0000000000..71fb8e8121
--- /dev/null
+++ b/devtools/client/shared/sourceeditor/codemirror/addon/fold/markdown-fold.js
@@ -0,0 +1,49 @@
+// CodeMirror, copyright (c) by Marijn Haverbeke and others
+// Distributed under an MIT license: https://codemirror.net/LICENSE
+
+(function(mod) {
+  if (typeof exports == "object" && typeof module == "object") // CommonJS
+    mod(require("devtools/client/shared/sourceeditor/codemirror/lib/codemirror"));
+  else if (typeof define == "function" && define.amd) // AMD
+    define(["../../lib/codemirror"], mod);
+  else // Plain browser env
+    mod(CodeMirror);
+})(function(CodeMirror) {
+"use strict";
+
+CodeMirror.registerHelper("fold", "markdown", function(cm, start) {
+  var maxDepth = 100;
+
+  function isHeader(lineNo) {
+    var tokentype = cm.getTokenTypeAt(CodeMirror.Pos(lineNo, 0));
+    return tokentype && /\bheader\b/.test(tokentype);
+  }
+
+  function headerLevel(lineNo, line, nextLine) {
+    var match = line && line.match(/^#+/);
+    if (match && isHeader(lineNo)) return match[0].length;
+    match = nextLine && nextLine.match(/^[=\-]+\s*$/);
+    if (match && isHeader(lineNo + 1)) return nextLine[0] == "=" ? 1 : 2;
+    return maxDepth;
+  }
+
+  var firstLine = cm.getLine(start.line), nextLine = cm.getLine(start.line + 1);
+  var level = headerLevel(start.line, firstLine, nextLine);
+  if (level === maxDepth) return undefined;
+
+  var lastLineNo = cm.lastLine();
+  var end = start.line, nextNextLine = cm.getLine(end + 2);
+  while (end < lastLineNo) {
+    if (headerLevel(end + 1, nextLine, nextNextLine) <= level) break;
+    ++end;
+    nextLine = nextNextLine;
+    nextNextLine = cm.getLine(end + 2);
+  }
+
+  return {
+    from: CodeMirror.Pos(start.line, firstLine.length),
+    to: CodeMirror.Pos(end, cm.getLine(end).length)
+  };
+});
+
+});
diff --git a/devtools/client/shared/sourceeditor/codemirror/addon/fold/xml-fold.js b/devtools/client/shared/sourceeditor/codemirror/addon/fold/xml-fold.js
new file mode 100644
index 0000000000..5d5b1ff6e6
--- /dev/null
+++ b/devtools/client/shared/sourceeditor/codemirror/addon/fold/xml-fold.js
@@ -0,0 +1,184 @@
+// CodeMirror, copyright (c) by Marijn Haverbeke and others
+// Distributed under an MIT license: https://codemirror.net/LICENSE
+
+(function(mod) {
+  if (typeof exports == "object" && typeof module == "object") // CommonJS
+    mod(require("devtools/client/shared/sourceeditor/codemirror/lib/codemirror"));
+  else if (typeof define == "function" && define.amd) // AMD
+    define(["../../lib/codemirror"], mod);
+  else // Plain browser env
+    mod(CodeMirror);
+})(function(CodeMirror) {
+  "use strict";
+
+  var Pos = CodeMirror.Pos;
+  function cmp(a, b) { return a.line - b.line || a.ch - b.ch; }
+
+  var nameStartChar = "A-Z_a-z\\u00C0-\\u00D6\\u00D8-\\u00F6\\u00F8-\\u02FF\\u0370-\\u037D\\u037F-\\u1FFF\\u200C-\\u200D\\u2070-\\u218F\\u2C00-\\u2FEF\\u3001-\\uD7FF\\uF900-\\uFDCF\\uFDF0-\\uFFFD";
+  var nameChar = nameStartChar + "\-\:\.0-9\\u00B7\\u0300-\\u036F\\u203F-\\u2040";
+  var xmlTagStart = new RegExp("<(/?)([" + nameStartChar + "][" + nameChar + "]*)", "g");
+
+  function Iter(cm, line, ch, range) {
+    this.line = line; this.ch = ch;
+    this.cm = cm; this.text = cm.getLine(line);
+    this.min = range ? Math.max(range.from, cm.firstLine()) : cm.firstLine();
+    this.max = range ? Math.min(range.to - 1, cm.lastLine()) : cm.lastLine();
+  }
+
+  function tagAt(iter, ch) {
+    var type = iter.cm.getTokenTypeAt(Pos(iter.line, ch));
+    return type && /\btag\b/.test(type);
+  }
+
+  function nextLine(iter) {
+    if (iter.line >= iter.max) return;
+    iter.ch = 0;
+    iter.text = iter.cm.getLine(++iter.line);
+    return true;
+  }
+  function prevLine(iter) {
+    if (iter.line <= iter.min) return;
+    iter.text = iter.cm.getLine(--iter.line);
+    iter.ch = iter.text.length;
+    return true;
+  }
+
+  function toTagEnd(iter) {
+    for (;;) {
+      var gt = iter.text.indexOf(">", iter.ch);
+      if (gt == -1) { if (nextLine(iter)) continue; else return; }
+      if (!tagAt(iter, gt + 1)) { iter.ch = gt + 1; continue; }
+      var lastSlash = iter.text.lastIndexOf("/", gt);
+      var selfClose = lastSlash > -1 && !/\S/.test(iter.text.slice(lastSlash + 1, gt));
+      iter.ch = gt + 1;
+      return selfClose ? "selfClose" : "regular";
+    }
+  }
+  function toTagStart(iter) {
+    for (;;) {
+      var lt = iter.ch ? iter.text.lastIndexOf("<", iter.ch - 1) : -1;
+      if (lt == -1) { if (prevLine(iter)) continue; else return; }
+      if (!tagAt(iter, lt + 1)) { iter.ch = lt; continue; }
+      xmlTagStart.lastIndex = lt;
+      iter.ch = lt;
+      var match = xmlTagStart.exec(iter.text);
+      if (match && match.index == lt) return match;
+    }
+  }
+
+  function toNextTag(iter) {
+    for (;;) {
+      xmlTagStart.lastIndex = iter.ch;
+      var found = xmlTagStart.exec(iter.text);
+      if (!found) { if (nextLine(iter)) continue; else return; }
+      if (!tagAt(iter, found.index + 1)) { iter.ch = found.index + 1; continue; }
+      iter.ch = found.index + found[0].length;
+      return found;
+    }
+  }
+  function toPrevTag(iter) {
+    for (;;) {
+      var gt = iter.ch ? iter.text.lastIndexOf(">", iter.ch - 1) : -1;
+      if (gt == -1) { if (prevLine(iter)) continue; else return; }
+      if (!tagAt(iter, gt + 1)) { iter.ch = gt; continue; }
+      var lastSlash = iter.text.lastIndexOf("/", gt);
+      var selfClose = lastSlash > -1 && !/\S/.test(iter.text.slice(lastSlash + 1, gt));
+      iter.ch = gt + 1;
+      return selfClose ? "selfClose" : "regular";
+    }
+  }
+
+  function findMatchingClose(iter, tag) {
+    var stack = [];
+    for (;;) {
+      var next = toNextTag(iter), end, startLine = iter.line, startCh = iter.ch - (next ? next[0].length : 0);
+      if (!next || !(end = toTagEnd(iter))) return;
+      if (end == "selfClose") continue;
+      if (next[1]) { // closing tag
+        for (var i = stack.length - 1; i >= 0; --i) if (stack[i] == next[2]) {
+          stack.length = i;
+          break;
+        }
+        if (i < 0 && (!tag || tag == next[2])) return {
+          tag: next[2],
+          from: Pos(startLine, startCh),
+          to: Pos(iter.line, iter.ch)
+        };
+      } else { // opening tag
+        stack.push(next[2]);
+      }
+    }
+  }
+  function findMatchingOpen(iter, tag) {
+    var stack = [];
+    for (;;) {
+      var prev = toPrevTag(iter);
+      if (!prev) return;
+      if (prev == "selfClose") { toTagStart(iter); continue; }
+      var endLine = iter.line, endCh = iter.ch;
+      var start = toTagStart(iter);
+      if (!start) return;
+      if (start[1]) { // closing tag
+        stack.push(start[2]);
+      } else { // opening tag
+        for (var i = stack.length - 1; i >= 0; --i) if (stack[i] == start[2]) {
+          stack.length = i;
+          break;
+        }
+        if (i < 0 && (!tag || tag == start[2])) return {
+          tag: start[2],
+          from: Pos(iter.line, iter.ch),
+          to: Pos(endLine, endCh)
+        };
+      }
+    }
+  }
+
+  CodeMirror.registerHelper("fold", "xml", function(cm, start) {
+    var iter = new Iter(cm, start.line, 0);
+    for (;;) {
+      var openTag = toNextTag(iter)
+      if (!openTag || iter.line != start.line) return
+      var end = toTagEnd(iter)
+      if (!end) return
+      if (!openTag[1] && end != "selfClose") {
+        var startPos = Pos(iter.line, iter.ch);
+        var endPos = findMatchingClose(iter, openTag[2]);
+        return endPos && cmp(endPos.from, startPos) > 0 ? {from: startPos, to: endPos.from} : null
+      }
+    }
+  });
+  CodeMirror.findMatchingTag = function(cm, pos, range) {
+    var iter = new Iter(cm, pos.line, pos.ch, range);
+    if (iter.text.indexOf(">") == -1 && iter.text.indexOf("<") == -1) return;
+    var end = toTagEnd(iter), to = end && Pos(iter.line, iter.ch);
+    var start = end && toTagStart(iter);
+    if (!end || !start || cmp(iter, pos) > 0) return;
+    var here = {from: Pos(iter.line, iter.ch), to: to, tag: start[2]};
+    if (end == "selfClose") return {open: here, close: null, at: "open"};
+
+    if (start[1]) { // closing tag
+      return {open: findMatchingOpen(iter, start[2]), close: here, at: "close"};
+    } else { // opening tag
+      iter = new Iter(cm, to.line, to.ch, range);
+      return {open: here, close: findMatchingClose(iter, start[2]), at: "open"};
+    }
+  };
+
+  CodeMirror.findEnclosingTag = function(cm, pos, range, tag) {
+    var iter = new Iter(cm, pos.line, pos.ch, range);
+    for (;;) {
+      var open = findMatchingOpen(iter, tag);
+      if (!open) break;
+      var forward = new Iter(cm, pos.line, pos.ch, range);
+      var close = findMatchingClose(forward, open.tag);
+      if (close) return {open: open, close: close};
+    }
+  };
+
+  // Used by addon/edit/closetag.js
+  CodeMirror.scanForClosingTag = function(cm, pos, name, end) {
+    var iter = new Iter(cm, pos.line, pos.ch, end ? {from: 0, to: end} : null);
+    return findMatchingClose(iter, name);
+  };
+});
diff --git a/devtools/client/shared/sourceeditor/codemirror/addon/runmode/runmode.js b/devtools/client/shared/sourceeditor/codemirror/addon/runmode/runmode.js
new file mode 100644
index 0000000000..e8d4b00f0b
--- /dev/null
+++ b/devtools/client/shared/sourceeditor/codemirror/addon/runmode/runmode.js
@@ -0,0 +1,72 @@
+// CodeMirror, copyright (c) by Marijn Haverbeke and others
+// Distributed under an MIT license: https://codemirror.net/LICENSE
+
+(function(mod) {
+  if (typeof exports == "object" && typeof module == "object") // CommonJS
+    mod(require("devtools/client/shared/sourceeditor/codemirror/lib/codemirror"));
+  else if (typeof define == "function" && define.amd) // AMD
+    define(["../../lib/codemirror"], mod);
+  else // Plain browser env
+    mod(CodeMirror);
+})(function(CodeMirror) {
+"use strict";
+
+CodeMirror.runMode = function(string, modespec, callback, options) {
+  var mode = CodeMirror.getMode(CodeMirror.defaults, modespec);
+  var ie = /MSIE \d/.test(navigator.userAgent);
+  var ie_lt9 = ie && (document.documentMode == null || document.documentMode < 9);
+
+  if (callback.appendChild) {
+    var tabSize = (options && options.tabSize) || CodeMirror.defaults.tabSize;
+    var node = callback, col = 0;
+    node.innerHTML = "";
+    callback = function(text, style) {
+      if (text == "\n") {
+        // Emitting LF or CRLF on IE8 or earlier results in an incorrect display.
+        // Emitting a carriage return makes everything ok.
+        node.appendChild(document.createTextNode(ie_lt9 ? '\r' : text));
+        col = 0;
+        return;
+      }
+      var content = "";
+      // replace tabs
+      for (var pos = 0;;) {
+        var idx = text.indexOf("\t", pos);
+        if (idx == -1) {
+          content += text.slice(pos);
+          col += text.length - pos;
+          break;
+        } else {
+          col += idx - pos;
+          content += text.slice(pos, idx);
+          var size = tabSize - col % tabSize;
+          col += size;
+          for (var i = 0; i < size; ++i) content += " ";
+          pos = idx + 1;
+        }
+      }
+
+      if (style) {
+        var sp = node.appendChild(document.createElement("span"));
+        sp.className = "cm-" + style.replace(/ +/g, " cm-");
+        sp.appendChild(document.createTextNode(content));
+      } else {
+        node.appendChild(document.createTextNode(content));
+      }
+    };
+  }
+
+  var lines = CodeMirror.splitLines(string), state = (options && options.state) || CodeMirror.startState(mode);
+  for (var i = 0, e = lines.length; i < e; ++i) {
+    if (i) callback("\n");
+    var stream = new CodeMirror.StringStream(lines[i]);
+    if (!stream.string && mode.blankLine) mode.blankLine(state);
+    while (!stream.eol()) {
+      var style = mode.token(stream, state);
+      callback(stream.current(), style, i, stream.start, state);
+      stream.start = stream.pos;
+    }
+  }
+};
+
+});
diff --git a/devtools/client/shared/sourceeditor/codemirror/addon/search/match-highlighter.js b/devtools/client/shared/sourceeditor/codemirror/addon/search/match-highlighter.js
new file mode 100644
index 0000000000..83d419ee25
--- /dev/null
+++ b/devtools/client/shared/sourceeditor/codemirror/addon/search/match-highlighter.js
@@ -0,0 +1,165 @@
+// CodeMirror, copyright (c) by Marijn Haverbeke and others
+// Distributed under an MIT license: https://codemirror.net/LICENSE
+
+// Highlighting text that matches the selection
+//
+// Defines an option highlightSelectionMatches, which, when enabled,
+// will style strings that match the selection throughout the
+// document.
+//
+// The option can be set to true to simply enable it, or to a
+// {minChars, style, wordsOnly, showToken, delay} object to explicitly
+// configure it. minChars is the minimum amount of characters that should be
+// selected for the behavior to occur, and style is the token style to
+// apply to the matches. This will be prefixed by "cm-" to create an
+// actual CSS class name. If wordsOnly is enabled, the matches will be
+// highlighted only if the selected text is a word. showToken, when enabled,
+// will cause the current token to be highlighted when nothing is selected.
+// delay is used to specify how much time to wait, in milliseconds, before
+// highlighting the matches. If annotateScrollbar is enabled, the occurences
+// will be highlighted on the scrollbar via the matchesonscrollbar addon.
+
+(function(mod) {
+  if (typeof exports == "object" && typeof module == "object") // CommonJS
+    mod(require("devtools/client/shared/sourceeditor/codemirror/lib/codemirror"), require("devtools/client/shared/sourceeditor/codemirror/addon/search/matchesonscrollbar"));
+  else if (typeof define == "function" && define.amd) // AMD
+    define(["../../lib/codemirror", "./matchesonscrollbar"], mod);
+  else // Plain browser env
+    mod(CodeMirror);
+})(function(CodeMirror) {
+  "use strict";
+
+  var defaults = {
+    style: "matchhighlight",
+    minChars: 2,
+    delay: 100,
+    wordsOnly: false,
+    annotateScrollbar: false,
+    showToken: false,
+    trim: true
+  }
+
+  function State(options) {
+    this.options = {}
+    for (var name in defaults)
+      this.options[name] = (options && options.hasOwnProperty(name) ? options : defaults)[name]
+    this.overlay = this.timeout = null;
+    this.matchesonscroll = null;
+    this.active = false;
+  }
+
+  CodeMirror.defineOption("highlightSelectionMatches", false, function(cm, val, old) {
+    if (old && old != CodeMirror.Init) {
+      removeOverlay(cm);
+      clearTimeout(cm.state.matchHighlighter.timeout);
+      cm.state.matchHighlighter = null;
+      cm.off("cursorActivity", cursorActivity);
+      cm.off("focus", onFocus)
+    }
+    if (val) {
+      var state = cm.state.matchHighlighter = new State(val);
+      if (cm.hasFocus()) {
+        state.active = true
+        highlightMatches(cm)
+      } else {
+        cm.on("focus", onFocus)
+      }
+      cm.on("cursorActivity", cursorActivity);
+    }
+  });
+
+  function cursorActivity(cm) {
+    var state = cm.state.matchHighlighter;
+    if (state.active || cm.hasFocus()) scheduleHighlight(cm, state)
+  }
+
+  function onFocus(cm) {
+    var state = cm.state.matchHighlighter
+    if (!state.active) {
+      state.active = true
+      scheduleHighlight(cm, state)
+    }
+  }
+
+  function scheduleHighlight(cm, state) {
+    clearTimeout(state.timeout);
+    state.timeout = setTimeout(function() {highlightMatches(cm);}, state.options.delay);
+  }
+
+  function addOverlay(cm, query, hasBoundary, style) {
+    var state = cm.state.matchHighlighter;
+    cm.addOverlay(state.overlay = makeOverlay(query, hasBoundary, style));
+    if (state.options.annotateScrollbar && cm.showMatchesOnScrollbar) {
+      var searchFor = hasBoundary ? new RegExp("\\b" + query.replace(/[\\\[.+*?(){|^$]/g, "\\$&") + "\\b") : query;
+      state.matchesonscroll = cm.showMatchesOnScrollbar(searchFor, false,
+        {className: "CodeMirror-selection-highlight-scrollbar"});
+    }
+  }
+
+  function removeOverlay(cm) {
+    var state = cm.state.matchHighlighter;
+    if (state.overlay) {
+      cm.removeOverlay(state.overlay);
+      state.overlay = null;
+      if (state.matchesonscroll) {
+        state.matchesonscroll.clear();
+        state.matchesonscroll = null;
+      }
+    }
+  }
+
+  function highlightMatches(cm) {
+    cm.operation(function() {
+      var state = cm.state.matchHighlighter;
+      removeOverlay(cm);
+      if (!cm.somethingSelected() && state.options.showToken) {
+        var re = state.options.showToken === true ? /[\w$]/ : state.options.showToken;
+        var cur = cm.getCursor(), line = cm.getLine(cur.line), start = cur.ch, end = start;
+        while (start && re.test(line.charAt(start - 1))) --start;
+        while (end < line.length && re.test(line.charAt(end))) ++end;
+        if (start < end)
+          addOverlay(cm, line.slice(start, end), re, state.options.style);
+        return;
+      }
+      var from = cm.getCursor("from"), to = cm.getCursor("to");
+      if (from.line != to.line) return;
+      if (state.options.wordsOnly && !isWord(cm, from, to)) return;
+      var selection = cm.getRange(from, to)
+      if (state.options.trim) selection = selection.replace(/^\s+|\s+$/g, "")
+      if (selection.length >= state.options.minChars)
+        addOverlay(cm, selection, false, state.options.style);
+    });
+  }
+
+  function isWord(cm, from, to) {
+    var str = cm.getRange(from, to);
+    if (str.match(/^\w+$/) !== null) {
+        if (from.ch > 0) {
+            var pos = {line: from.line, ch: from.ch - 1};
+            var chr = cm.getRange(pos, from);
+            if (chr.match(/\W/) === null) return false;
+        }
+        if (to.ch < cm.getLine(from.line).length) {
+            var pos = {line: to.line, ch: to.ch + 1};
+            var chr = cm.getRange(to, pos);
+            if (chr.match(/\W/) === null) return false;
+        }
+        return true;
+    } else return false;
+  }
+
+  function boundariesAround(stream, re) {
+    return (!stream.start || !re.test(stream.string.charAt(stream.start - 1))) &&
+      (stream.pos == stream.string.length || !re.test(stream.string.charAt(stream.pos)));
+  }
+
+  function makeOverlay(query, hasBoundary, style) {
+    return {token: function(stream) {
+      if (stream.match(query) &&
+          (!hasBoundary || boundariesAround(stream, hasBoundary)))
+        return style;
+      stream.next();
+      stream.skipTo(query.charAt(0)) || stream.skipToEnd();
+    }};
+  }
+});
diff --git a/devtools/client/shared/sourceeditor/codemirror/addon/search/search.js b/devtools/client/shared/sourceeditor/codemirror/addon/search/search.js
new file mode 100644
index 0000000000..240249dcd6
--- /dev/null
+++ b/devtools/client/shared/sourceeditor/codemirror/addon/search/search.js
@@ -0,0 +1,323 @@
+// CodeMirror, copyright (c) by Marijn Haverbeke and others
+// Distributed under an MIT license: https://codemirror.net/LICENSE
+
+// Define search commands. Depends on dialog.js or another
+// implementation of the openDialog method.
+
+// Replace works a little oddly -- it will do the replace on the next
+// Ctrl-G (or whatever is bound to findNext) press. You prevent a
+// replace by making sure the match is no longer selected when hitting
+// Ctrl-G.
+
+(function(mod) {
+  if (typeof exports == "object" && typeof module == "object") // CommonJS
+    mod(require("devtools/client/shared/sourceeditor/codemirror/lib/codemirror"), require("devtools/client/shared/sourceeditor/codemirror/addon/search/searchcursor"), require("devtools/client/shared/sourceeditor/codemirror/addon/dialog/dialog"));
+  else if (typeof define == "function" && define.amd) // AMD
+    define(["../../lib/codemirror", "./searchcursor", "../dialog/dialog"], mod);
+  else // Plain browser env
+    mod(CodeMirror);
+})(function(CodeMirror) {
+  "use strict";
+
+  function searchOverlay(query, caseInsensitive) {
+    if (typeof query == "string")
+      query = new RegExp(query.replace(/[\-\[\]\/\{\}\(\)\*\+\?\.\\\^\$\|]/g, "\\$&"), caseInsensitive ? "gi" : "g");
+    else if (!query.global)
+      query = new RegExp(query.source, query.ignoreCase ? "gi" : "g");
+
+    return {token: function(stream) {
+      query.lastIndex = stream.pos;
+      var match = query.exec(stream.string);
+      if (match && match.index == stream.pos) {
+        stream.pos += match[0].length || 1;
+        return "searching";
+      } else if (match) {
+        stream.pos = match.index;
+      } else {
+        stream.skipToEnd();
+      }
+    }};
+  }
+
+  function SearchState() {
+    this.posFrom = this.posTo = this.lastQuery = this.query = null;
+    this.overlay = null;
+  }
+
+  function getSearchState(cm) {
+    return cm.state.search || (cm.state.search = new SearchState());
+  }
+
+  function queryCaseInsensitive(query) {
+    return typeof query == "string" && query == query.toLowerCase();
+  }
+
+  function getSearchCursor(cm, query, pos) {
+    // Heuristic: if the query string is all lowercase, do a case insensitive search.
+    return cm.getSearchCursor(query, pos, {caseFold: queryCaseInsensitive(query), multiline: true});
+  }
+
+  function persistentDialog(cm, text, deflt, onEnter, onKeyDown) {
+    cm.openDialog(text, onEnter, {
+      value: deflt,
+      selectValueOnOpen: true,
+      closeOnEnter: false,
+      onClose: function() { clearSearch(cm); },
+      onKeyDown: onKeyDown
+    });
+  }
+
+  function dialog(cm, text, shortText, deflt, f) {
+    if (cm.openDialog) cm.openDialog(text, f, {value: deflt, selectValueOnOpen: true});
+    else f(prompt(shortText, deflt));
+  }
+
+  function confirmDialog(cm, text, shortText, fs) {
+    if (cm.openConfirm) cm.openConfirm(text, fs);
+    else if (confirm(shortText)) fs[0]();
+  }
+
+  function parseString(string) {
+    return string.replace(/\\([nrt\\])/g, function(match, ch) {
+      if (ch == "n") return "\n"
+      if (ch == "r") return "\r"
+      if (ch == "t") return "\t"
+      if (ch == "\\") return "\\"
+      return match
+    })
+  }
+
+  function parseQuery(query) {
+    var isRE = query.match(/^\/(.*)\/([a-z]*)$/);
+    if (isRE) {
+      try { query = new RegExp(isRE[1], isRE[2].indexOf("i") == -1 ? "" : "i"); }
+      catch(e) {} // Not a regular expression after all, do a string search
+    } else {
+      query = parseString(query)
+    }
+    if (typeof query == "string" ? query == "" : query.test(""))
+      query = /x^/;
+    return query;
+  }
+
+  var queryDialog;
+
+  function startSearch(cm, state, query) {
+    state.queryText = query;
+    state.query = parseQuery(query);
+    cm.removeOverlay(state.overlay, queryCaseInsensitive(state.query));
+    state.overlay = searchOverlay(state.query, queryCaseInsensitive(state.query));
+    cm.addOverlay(state.overlay);
+    if (cm.showMatchesOnScrollbar) {
+      if (state.annotate) { state.annotate.clear(); state.annotate = null; }
+      state.annotate = cm.showMatchesOnScrollbar(state.query, queryCaseInsensitive(state.query));
+    }
+  }
+
+  function doSearch(cm, rev, persistent, immediate) {
+    if (!queryDialog) {
+      let doc = cm.getWrapperElement().ownerDocument;
+      let inp = doc.createElement("input");
+
+      inp.type = "search";
+      inp.placeholder = cm.l10n("findCmd.promptMessage");
+      inp.style.marginInlineStart = "1em";
+      inp.style.marginInlineEnd = "1em";
+      inp.style.flexGrow = "1";
+      inp.addEventListener("focus", () => inp.select());
+
+      queryDialog = doc.createElement("div");
+      queryDialog.appendChild(inp);
+      queryDialog.style.display = "flex";
+    }
+
+    var state = getSearchState(cm);
+    if (state.query) return findNext(cm, rev);
+    var q = cm.getSelection() || state.lastQuery;
+    if (q instanceof RegExp && q.source == "x^") q = null
+    if (persistent && cm.openDialog) {
+      var hiding = null
+      var searchNext = function(query, event) {
+        CodeMirror.e_stop(event);
+        if (!query) return;
+        if (query != state.queryText) {
+          startSearch(cm, state, query);
+          state.posFrom = state.posTo = cm.getCursor();
+        }
+        if (hiding) hiding.style.opacity = 1
+        findNext(cm, event.shiftKey, function(_, to) {
+          var dialog
+          if (to.line < 3 && document.querySelector &&
+              (dialog = cm.display.wrapper.querySelector(".CodeMirror-dialog")) &&
+              dialog.getBoundingClientRect().bottom - 4 > cm.cursorCoords(to, "window").top)
+            (hiding = dialog).style.opacity = .4
+        })
+      };
+      persistentDialog(cm, queryDialog, q, searchNext, function(event, query) {
+        var keyName = CodeMirror.keyName(event)
+        var extra = cm.getOption('extraKeys'), cmd = (extra && extra[keyName]) || CodeMirror.keyMap[cm.getOption("keyMap")][keyName]
+        if (cmd == "findNext" || cmd == "findPrev" ||
+          cmd == "findPersistentNext" || cmd == "findPersistentPrev") {
+          CodeMirror.e_stop(event);
+          startSearch(cm, getSearchState(cm), query);
+          cm.execCommand(cmd);
+        } else if (cmd == "find" || cmd == "findPersistent") {
+          CodeMirror.e_stop(event);
+          searchNext(query, event);
+        }
+      });
+      if (immediate && q) {
+        startSearch(cm, state, q);
+        findNext(cm, rev);
+      }
+    } else {
+      dialog(cm, queryDialog, "Search for:", q, function(query) {
+        if (query && !state.query) cm.operation(function() {
+          startSearch(cm, state, query);
+          state.posFrom = state.posTo = cm.getCursor();
+          findNext(cm, rev);
+        });
+      });
+    }
+  }
+
+  function findNext(cm, rev, callback) {cm.operation(function() {
+    var state = getSearchState(cm);
+    var cursor = getSearchCursor(cm, state.query, rev ? state.posFrom : state.posTo);
+    if (!cursor.find(rev)) {
+      cursor = getSearchCursor(cm, state.query, rev ? CodeMirror.Pos(cm.lastLine()) : CodeMirror.Pos(cm.firstLine(), 0));
+      if (!cursor.find(rev)) return;
+    }
+    cm.setSelection(cursor.from(), cursor.to());
+    cm.scrollIntoView({from: cursor.from(), to: cursor.to()}, 20);
+    state.posFrom = cursor.from(); state.posTo = cursor.to();
+    if (callback) callback(cursor.from(), cursor.to())
+  });}
+
+  function clearSearch(cm) {cm.operation(function() {
+    var state = getSearchState(cm);
+    state.lastQuery = state.query;
+    if (!state.query) return;
+    state.query = state.queryText = null;
+    cm.removeOverlay(state.overlay);
+    if (state.annotate) { state.annotate.clear(); state.annotate = null; }
+  });}
+
+  function replaceAll(cm, query, text) {
+    cm.operation(function() {
+      for (var cursor = getSearchCursor(cm, query); cursor.findNext();) {
+        if (typeof query != "string") {
+          var match = cm.getRange(cursor.from(), cursor.to()).match(query);
+          cursor.replace(text.replace(/\$(\d)/g, function(_, i) {return match[i];}));
+        } else cursor.replace(text);
+      }
+    });
+  }
+
+  function replace(cm, all) {
+    if (cm.getOption("readOnly")) return;
+    var query = cm.getSelection() || getSearchState(cm).lastQuery;
+
+    let doc = cm.getWrapperElement().ownerDocument;
+
+    // `searchLabel` is used as part of `replaceQueryFragment` and as a separate
+    // argument by itself, so it should be cloned.
+    let searchLabel = doc.createElement("span");
+    searchLabel.classList.add("CodeMirror-search-label");
+    searchLabel.textContent = all ? "Replace all:" : "Replace:";
+
+    let replaceQueryFragment = doc.createDocumentFragment();
+    replaceQueryFragment.appendChild(searchLabel.cloneNode(true));
+
+    let searchField = doc.createElement("input");
+    searchField.setAttribute("type", "text");
+    searchField.setAttribute("style", "width: 10em");
+    searchField.classList.add("CodeMirror-search-field");
+    replaceQueryFragment.appendChild(searchField);
+
+    let searchHint = doc.createElement("span");
+    searchHint.setAttribute("style", "color: #888");
+    searchHint.classList.add("CodeMirror-search-hint");
+    searchHint.textContent = "(Use /re/ syntax for regexp search)";
+    replaceQueryFragment.appendChild(searchHint);
+
+    dialog(cm, replaceQueryFragment, searchLabel, query, function(query) {
+      if (!query) return;
+      query = parseQuery(query);
+
+      let replacementQueryFragment = doc.createDocumentFragment();
+
+      let replaceWithLabel = searchLabel.cloneNode(false);
+      replaceWithLabel.textContent = "With:";
+      replacementQueryFragment.appendChild(replaceWithLabel);
+
+      let replaceField = doc.createElement("input");
+      replaceField.setAttribute("type", "text");
+      replaceField.setAttribute("style", "width: 10em");
+      replaceField.classList.add("CodeMirror-search-field");
+      replacementQueryFragment.appendChild(replaceField);
+
+      dialog(cm, replacementQueryFragment, "Replace with:", "", function(text) {
+        text = parseString(text)
+        if (all) {
+          replaceAll(cm, query, text)
+        } else {
+          clearSearch(cm);
+          var cursor = getSearchCursor(cm, query, cm.getCursor("from"));
+          var advance = function() {
+            var start = cursor.from(), match;
+            if (!(match = cursor.findNext())) {
+              cursor = getSearchCursor(cm, query);
+              if (!(match = cursor.findNext()) ||
+                  (start && cursor.from().line == start.line && cursor.from().ch == start.ch)) return;
+            }
+            cm.setSelection(cursor.from(), cursor.to());
+            cm.scrollIntoView({ from: cursor.from(), to: cursor.to() });
+
+            let replaceConfirmFragment = doc.createDocumentFragment();
+
+            let replaceConfirmLabel = searchLabel.cloneNode(false);
+            replaceConfirmLabel.textContent = "Replace?";
+            replaceConfirmFragment.appendChild(replaceConfirmLabel);
+
+            let yesButton = doc.createElement("button");
+            yesButton.textContent = "Yes";
+            replaceConfirmFragment.appendChild(yesButton);
+
+            let noButton = doc.createElement("button");
+            noButton.textContent = "No";
+            replaceConfirmFragment.appendChild(noButton);
+
+            let allButton = doc.createElement("button");
+            allButton.textContent = "All";
+            replaceConfirmFragment.appendChild(allButton);
+
+            let stopButton = doc.createElement("button");
+            stopButton.textContent = "Stop";
+            replaceConfirmFragment.appendChild(stopButton);
+
+            confirmDialog(cm, replaceConfirmFragment, "Replace?",
+                          [function() {doReplace(match);}, advance,
+                           function() {replaceAll(cm, query, text)}]);
+          };
+          var doReplace = function(match) {
+            cursor.replace(typeof query == "string" ? text :
+                           text.replace(/\$(\d)/g, function(_, i) {return match[i];}));
+            advance();
+          };
+          advance();
+        }
+      });
+    });
+  }
+
+  CodeMirror.commands.find = function(cm) {clearSearch(cm); doSearch(cm);};
+  CodeMirror.commands.findPersistent = function(cm) {clearSearch(cm); doSearch(cm, false, true);};
+  CodeMirror.commands.findPersistentNext = function(cm) {doSearch(cm, false, true, true);};
+  CodeMirror.commands.findPersistentPrev = function(cm) {doSearch(cm, true, true, true);};
+  CodeMirror.commands.findNext = doSearch;
+  CodeMirror.commands.findPrev = function(cm) {doSearch(cm, true);};
+  CodeMirror.commands.clearSearch = clearSearch;
+  CodeMirror.commands.replace = replace;
+  CodeMirror.commands.replaceAll = function(cm) {replace(cm, true);};
+});
diff --git a/devtools/client/shared/sourceeditor/codemirror/addon/search/searchcursor.js b/devtools/client/shared/sourceeditor/codemirror/addon/search/searchcursor.js
new file mode 100644
index 0000000000..c715ea4cce
--- /dev/null
+++ b/devtools/client/shared/sourceeditor/codemirror/addon/search/searchcursor.js
@@ -0,0 +1,293 @@
+// CodeMirror, copyright (c) by Marijn Haverbeke and others
+// Distributed under an MIT license: https://codemirror.net/LICENSE
+
+(function(mod) {
+  if (typeof exports == "object" && typeof module == "object") // CommonJS
+    mod(require("devtools/client/shared/sourceeditor/codemirror/lib/codemirror"))
+  else if (typeof define == "function" && define.amd) // AMD
+    define(["../../lib/codemirror"], mod)
+  else // Plain browser env
+    mod(CodeMirror)
+})(function(CodeMirror) {
+  "use strict"
+  var Pos = CodeMirror.Pos
+
+  function regexpFlags(regexp) {
+    var flags = regexp.flags
+    return flags != null ? flags : (regexp.ignoreCase ? "i" : "")
+      + (regexp.global ? "g" : "")
+      + (regexp.multiline ? "m" : "")
+  }
+
+  function ensureFlags(regexp, flags) {
+    var current = regexpFlags(regexp), target = current
+    for (var i = 0; i < flags.length; i++) if (target.indexOf(flags.charAt(i)) == -1)
+      target += flags.charAt(i)
+    return current == target ? regexp : new RegExp(regexp.source, target)
+  }
+
+  function maybeMultiline(regexp) {
+    return /\\s|\\n|\n|\\W|\\D|\[\^/.test(regexp.source)
+  }
+
+  function searchRegexpForward(doc, regexp, start) {
+    regexp = ensureFlags(regexp, "g")
+    for (var line = start.line, ch = start.ch, last = doc.lastLine(); line <= last; line++, ch = 0) {
+      regexp.lastIndex = ch
+      var string = doc.getLine(line), match = regexp.exec(string)
+      if (match)
+        return {from: Pos(line, match.index),
+                to: Pos(line, match.index + match[0].length),
+                match: match}
+    }
+  }
+
+  function searchRegexpForwardMultiline(doc, regexp, start) {
+    if (!maybeMultiline(regexp)) return searchRegexpForward(doc, regexp, start)
+
+    regexp = ensureFlags(regexp, "gm")
+    var string, chunk = 1
+    for (var line = start.line, last = doc.lastLine(); line <= last;) {
+      // This grows the search buffer in exponentially-sized chunks
+      // between matches, so that nearby matches are fast and don't
+      // require concatenating the whole document (in case we're
+      // searching for something that has tons of matches), but at the
+      // same time, the amount of retries is limited.
+      for (var i = 0; i < chunk; i++) {
+        if (line > last) break
+        var curLine = doc.getLine(line++)
+        string = string == null ? curLine : string + "\n" + curLine
+      }
+      chunk = chunk * 2
+      regexp.lastIndex = start.ch
+      var match = regexp.exec(string)
+      if (match) {
+        var before = string.slice(0, match.index).split("\n"), inside = match[0].split("\n")
+        var startLine = start.line + before.length - 1, startCh = before[before.length - 1].length
+        return {from: Pos(startLine, startCh),
+                to: Pos(startLine + inside.length - 1,
+                        inside.length == 1 ? startCh + inside[0].length : inside[inside.length - 1].length),
+                match: match}
+      }
+    }
+  }
+
+  function lastMatchIn(string, regexp) {
+    var cutOff = 0, match
+    for (;;) {
+      regexp.lastIndex = cutOff
+      var newMatch = regexp.exec(string)
+      if (!newMatch) return match
+      match = newMatch
+      cutOff = match.index + (match[0].length || 1)
+      if (cutOff == string.length) return match
+    }
+  }
+
+  function searchRegexpBackward(doc, regexp, start) {
+    regexp = ensureFlags(regexp, "g")
+    for (var line = start.line, ch = start.ch, first = doc.firstLine(); line >= first; line--, ch = -1) {
+      var string = doc.getLine(line)
+      if (ch > -1) string = string.slice(0, ch)
+      var match = lastMatchIn(string, regexp)
+      if (match)
+        return {from: Pos(line, match.index),
+                to: Pos(line, match.index + match[0].length),
+                match: match}
+    }
+  }
+
+  function searchRegexpBackwardMultiline(doc, regexp, start) {
+    regexp = ensureFlags(regexp, "gm")
+    var string, chunk = 1
+    for (var line = start.line, first = doc.firstLine(); line >= first;) {
+      for (var i = 0; i < chunk; i++) {
+        var curLine = doc.getLine(line--)
+        string = string == null ? curLine.slice(0, start.ch) : curLine + "\n" + string
+      }
+      chunk *= 2
+
+      var match = lastMatchIn(string, regexp)
+      if (match) {
+        var before = string.slice(0, match.index).split("\n"), inside = match[0].split("\n")
+        var startLine = line + before.length, startCh = before[before.length - 1].length
+        return {from: Pos(startLine, startCh),
+                to: Pos(startLine + inside.length - 1,
+                        inside.length == 1 ? startCh + inside[0].length : inside[inside.length - 1].length),
+                match: match}
+      }
+    }
+  }
+
+  var doFold, noFold
+  if (String.prototype.normalize) {
+    doFold = function(str) { return str.normalize("NFD").toLowerCase() }
+    noFold = function(str) { return str.normalize("NFD") }
+  } else {
+    doFold = function(str) { return str.toLowerCase() }
+    noFold = function(str) { return str }
+  }
+
+  // Maps a position in a case-folded line back to a position in the original line
+  // (compensating for codepoints increasing in number during folding)
+  function adjustPos(orig, folded, pos, foldFunc) {
+    if (orig.length == folded.length) return pos
+    for (var min = 0, max = pos + Math.max(0, orig.length - folded.length);;) {
+      if (min == max) return min
+      var mid = (min + max) >> 1
+      var len = foldFunc(orig.slice(0, mid)).length
+      if (len == pos) return mid
+      else if (len > pos) max = mid
+      else min = mid + 1
+    }
+  }
+
+  function searchStringForward(doc, query, start, caseFold) {
+    // Empty string would match anything and never progress, so we
+    // define it to match nothing instead.
+    if (!query.length) return null
+    var fold = caseFold ? doFold : noFold
+    var lines = fold(query).split(/\r|\n\r?/)
+
+    search: for (var line = start.line, ch = start.ch, last = doc.lastLine() + 1 - lines.length; line <= last; line++, ch = 0) {
+      var orig = doc.getLine(line).slice(ch), string = fold(orig)
+      if (lines.length == 1) {
+        var found = string.indexOf(lines[0])
+        if (found == -1) continue search
+        var start = adjustPos(orig, string, found, fold) + ch
+        return {from: Pos(line, adjustPos(orig, string, found, fold) + ch),
+                to: Pos(line, adjustPos(orig, string, found + lines[0].length, fold) + ch)}
+      } else {
+        var cutFrom = string.length - lines[0].length
+        if (string.slice(cutFrom) != lines[0]) continue search
+        for (var i = 1; i < lines.length - 1; i++)
+          if (fold(doc.getLine(line + i)) != lines[i]) continue search
+        var end = doc.getLine(line + lines.length - 1), endString = fold(end), lastLine = lines[lines.length - 1]
+        if (endString.slice(0, lastLine.length) != lastLine) continue search
+        return {from: Pos(line, adjustPos(orig, string, cutFrom, fold) + ch),
+                to: Pos(line + lines.length - 1, adjustPos(end, endString, lastLine.length, fold))}
+      }
+    }
+  }
+
+  function searchStringBackward(doc, query, start, caseFold) {
+    if (!query.length) return null
+    var fold = caseFold ? doFold : noFold
+    var lines = fold(query).split(/\r|\n\r?/)
+
+    search: for (var line = start.line, ch = start.ch, first = doc.firstLine() - 1 + lines.length; line >= first; line--, ch = -1) {
+      var orig = doc.getLine(line)
+      if (ch > -1) orig = orig.slice(0, ch)
+      var string = fold(orig)
+      if (lines.length == 1) {
+        var found = string.lastIndexOf(lines[0])
+        if (found == -1) continue search
+        return {from: Pos(line, adjustPos(orig, string, found, fold)),
+                to: Pos(line, adjustPos(orig, string, found + lines[0].length, fold))}
+      } else {
+        var lastLine = lines[lines.length - 1]
+        if (string.slice(0, lastLine.length) != lastLine) continue search
+        for (var i = 1, start = line - lines.length + 1; i < lines.length - 1; i++)
+          if (fold(doc.getLine(start + i)) != lines[i]) continue search
+        var top = doc.getLine(line + 1 - lines.length), topString = fold(top)
+        if (topString.slice(topString.length - lines[0].length) != lines[0]) continue search
+        return {from: Pos(line + 1 - lines.length, adjustPos(top, topString, top.length - lines[0].length, fold)),
+                to: Pos(line, adjustPos(orig, string, lastLine.length, fold))}
+      }
+    }
+  }
+
+  function SearchCursor(doc, query, pos, options) {
+    this.atOccurrence = false
+    this.doc = doc
+    pos = pos ? doc.clipPos(pos) : Pos(0, 0)
+    this.pos = {from: pos, to: pos}
+
+    var caseFold
+    if (typeof options == "object") {
+      caseFold = options.caseFold
+    } else { // Backwards compat for when caseFold was the 4th argument
+      caseFold = options
+      options = null
+    }
+
+    if (typeof query == "string") {
+      if (caseFold == null) caseFold = false
+      this.matches = function(reverse, pos) {
+        return (reverse ? searchStringBackward : searchStringForward)(doc, query, pos, caseFold)
+      }
+    } else {
+      query = ensureFlags(query, "gm")
+      if (!options || options.multiline !== false)
+        this.matches = function(reverse, pos) {
+          return (reverse ? searchRegexpBackwardMultiline : searchRegexpForwardMultiline)(doc, query, pos)
+        }
+      else
+        this.matches = function(reverse, pos) {
+          return (reverse ? searchRegexpBackward : searchRegexpForward)(doc, query, pos)
+        }
+    }
+  }
+
+  SearchCursor.prototype = {
+    findNext: function() {return this.find(false)},
+    findPrevious: function() {return this.find(true)},
+
+    find: function(reverse) {
+      var result = this.matches(reverse, this.doc.clipPos(reverse ? this.pos.from : this.pos.to))
+
+      // Implements weird auto-growing behavior on null-matches for
+      // backwards-compatiblity with the vim code (unfortunately)
+      while (result && CodeMirror.cmpPos(result.from, result.to) == 0) {
+        if (reverse) {
+          if (result.from.ch) result.from = Pos(result.from.line, result.from.ch - 1)
+          else if (result.from.line == this.doc.firstLine()) result = null
+          else result = this.matches(reverse, this.doc.clipPos(Pos(result.from.line - 1)))
+        } else {
+          if (result.to.ch < this.doc.getLine(result.to.line).length) result.to = Pos(result.to.line, result.to.ch + 1)
+          else if (result.to.line == this.doc.lastLine()) result = null
+          else result = this.matches(reverse, Pos(result.to.line + 1, 0))
+        }
+      }
+
+      if (result) {
+        this.pos = result
+        this.atOccurrence = true
+        return this.pos.match || true
+      } else {
+        var end = Pos(reverse ? this.doc.firstLine() : this.doc.lastLine() + 1, 0)
+        this.pos = {from: end, to: end}
+        return this.atOccurrence = false
+      }
+    },
+
+    from: function() {if (this.atOccurrence) return this.pos.from},
+    to: function() {if (this.atOccurrence) return this.pos.to},
+
+    replace: function(newText, origin) {
+      if (!this.atOccurrence) return
+      var lines = CodeMirror.splitLines(newText)
+      this.doc.replaceRange(lines, this.pos.from, this.pos.to, origin)
+      this.pos.to = Pos(this.pos.from.line + lines.length - 1,
+                        lines[lines.length - 1].length + (lines.length == 1 ? this.pos.from.ch : 0))
+    }
+  }
+
+  CodeMirror.defineExtension("getSearchCursor", function(query, pos, caseFold) {
+    return new SearchCursor(this.doc, query, pos, caseFold)
+  })
+  CodeMirror.defineDocExtension("getSearchCursor", function(query, pos, caseFold) {
+    return new SearchCursor(this, query, pos, caseFold)
+  })
+
+  CodeMirror.defineExtension("selectMatches", function(query, caseFold) {
+    var ranges = []
+    var cur = this.getSearchCursor(query, this.getCursor("from"), caseFold)
+    while (cur.findNext()) {
+      if (CodeMirror.cmpPos(cur.to(), this.getCursor("to")) > 0) break
+      ranges.push({anchor: cur.from(), head: cur.to()})
+    }
+    if (ranges.length)
+      this.setSelections(ranges, 0)
+  })
+});
diff --git a/devtools/client/shared/sourceeditor/codemirror/addon/selection/active-line.js b/devtools/client/shared/sourceeditor/codemirror/addon/selection/active-line.js
new file mode 100644
index 0000000000..f151f209f0
--- /dev/null
+++ b/devtools/client/shared/sourceeditor/codemirror/addon/selection/active-line.js
@@ -0,0 +1,72 @@
+// CodeMirror, copyright (c) by Marijn Haverbeke and others
+// Distributed under an MIT license: https://codemirror.net/LICENSE
+
+(function(mod) {
+  if (typeof exports == "object" && typeof module == "object") // CommonJS
+    mod(require("devtools/client/shared/sourceeditor/codemirror/lib/codemirror"));
+  else if (typeof define == "function" && define.amd) // AMD
+    define(["../../lib/codemirror"], mod);
+  else // Plain browser env
+    mod(CodeMirror);
+})(function(CodeMirror) {
+  "use strict";
+  var WRAP_CLASS = "CodeMirror-activeline";
+  var BACK_CLASS = "CodeMirror-activeline-background";
+  var GUTT_CLASS = "CodeMirror-activeline-gutter";
+
+  CodeMirror.defineOption("styleActiveLine", false, function(cm, val, old) {
+    var prev = old == CodeMirror.Init ? false : old;
+    if (val == prev) return
+    if (prev) {
+      cm.off("beforeSelectionChange", selectionChange);
+      clearActiveLines(cm);
+      delete cm.state.activeLines;
+    }
+    if (val) {
+      cm.state.activeLines = [];
+      updateActiveLines(cm, cm.listSelections());
+      cm.on("beforeSelectionChange", selectionChange);
+    }
+  });
+
+  function clearActiveLines(cm) {
+    for (var i = 0; i < cm.state.activeLines.length; i++) {
+      cm.removeLineClass(cm.state.activeLines[i], "wrap", WRAP_CLASS);
+      cm.removeLineClass(cm.state.activeLines[i], "background", BACK_CLASS);
+      cm.removeLineClass(cm.state.activeLines[i], "gutter", GUTT_CLASS);
+    }
+  }
+
+  function sameArray(a, b) {
+    if (a.length != b.length) return false;
+    for (var i = 0; i < a.length; i++)
+      if (a[i] != b[i]) return false;
+    return true;
+  }
+
+  function updateActiveLines(cm, ranges) {
+    var active = [];
+    for (var i = 0; i < ranges.length; i++) {
+      var range = ranges[i];
+      var option = cm.getOption("styleActiveLine");
+      if (typeof option == "object" && option.nonEmpty ? range.anchor.line != range.head.line : !range.empty())
+        continue
+      var line = cm.getLineHandleVisualStart(range.head.line);
+      if (active[active.length - 1] != line) active.push(line);
+    }
+    if (sameArray(cm.state.activeLines, active)) return;
+    cm.operation(function() {
+      clearActiveLines(cm);
+      for (var i = 0; i < active.length; i++) {
+        cm.addLineClass(active[i], "wrap", WRAP_CLASS);
+        cm.addLineClass(active[i], "background", BACK_CLASS);
+        cm.addLineClass(active[i], "gutter", GUTT_CLASS);
+      }
+      cm.state.activeLines = active;
+    });
+  }
+
+  function selectionChange(cm, sel) {
+    updateActiveLines(cm, sel.ranges);
+  }
+});
diff --git a/devtools/client/shared/sourceeditor/codemirror/addon/selection/mark-selection.js b/devtools/client/shared/sourceeditor/codemirror/addon/selection/mark-selection.js
new file mode 100644
index 0000000000..cd1ed98964
--- /dev/null
+++ b/devtools/client/shared/sourceeditor/codemirror/addon/selection/mark-selection.js
@@ -0,0 +1,119 @@
+// CodeMirror, copyright (c) by Marijn Haverbeke and others
+// Distributed under an MIT license: https://codemirror.net/LICENSE
+
+// Because sometimes you need to mark the selected *text*.
+//
+// Adds an option 'styleSelectedText' which, when enabled, gives
+// selected text the CSS class given as option value, or
+// "CodeMirror-selectedtext" when the value is not a string.
+
+(function(mod) {
+  if (typeof exports == "object" && typeof module == "object") // CommonJS
+    mod(require("devtools/client/shared/sourceeditor/codemirror/lib/codemirror"));
+  else if (typeof define == "function" && define.amd) // AMD
+    define(["../../lib/codemirror"], mod);
+  else // Plain browser env
+    mod(CodeMirror);
+})(function(CodeMirror) {
+  "use strict";
+
+  CodeMirror.defineOption("styleSelectedText", false, function(cm, val, old) {
+    var prev = old && old != CodeMirror.Init;
+    if (val && !prev) {
+      cm.state.markedSelection = [];
+      cm.state.markedSelectionStyle = typeof val == "string" ? val : "CodeMirror-selectedtext";
+      reset(cm);
+      cm.on("cursorActivity", onCursorActivity);
+      cm.on("change", onChange);
+    } else if (!val && prev) {
+      cm.off("cursorActivity", onCursorActivity);
+      cm.off("change", onChange);
+      clear(cm);
+      cm.state.markedSelection = cm.state.markedSelectionStyle = null;
+    }
+  });
+
+  function onCursorActivity(cm) {
+    if (cm.state.markedSelection)
+      cm.operation(function() { update(cm); });
+  }
+
+  function onChange(cm) {
+    if (cm.state.markedSelection && cm.state.markedSelection.length)
+      cm.operation(function() { clear(cm); });
+  }
+
+  var CHUNK_SIZE = 8;
+  var Pos = CodeMirror.Pos;
+  var cmp = CodeMirror.cmpPos;
+
+  function coverRange(cm, from, to, addAt) {
+    if (cmp(from, to) == 0) return;
+    var array = cm.state.markedSelection;
+    var cls = cm.state.markedSelectionStyle;
+    for (var line = from.line;;) {
+      var start = line == from.line ? from : Pos(line, 0);
+      var endLine = line + CHUNK_SIZE, atEnd = endLine >= to.line;
+      var end = atEnd ? to : Pos(endLine, 0);
+      var mark = cm.markText(start, end, {className: cls});
+      if (addAt == null) array.push(mark);
+      else array.splice(addAt++, 0, mark);
+      if (atEnd) break;
+      line = endLine;
+    }
+  }
+
+  function clear(cm) {
+    var array = cm.state.markedSelection;
+    for (var i = 0; i < array.length; ++i) array[i].clear();
+    array.length = 0;
+  }
+
+  function reset(cm) {
+    clear(cm);
+    var ranges = cm.listSelections();
+    for (var i = 0; i < ranges.length; i++)
+      coverRange(cm, ranges[i].from(), ranges[i].to());
+  }
+
+  function update(cm) {
+    if (!cm.somethingSelected()) return clear(cm);
+    if (cm.listSelections().length > 1) return reset(cm);
+
+    var from = cm.getCursor("start"), to = cm.getCursor("end");
+
+    var array = cm.state.markedSelection;
+    if (!array.length) return coverRange(cm, from, to);
+
+    var coverStart = array[0].find(), coverEnd = array[array.length - 1].find();
+    if (!coverStart || !coverEnd || to.line - from.line <= CHUNK_SIZE ||
+        cmp(from, coverEnd.to) >= 0 || cmp(to, coverStart.from) <= 0)
+      return reset(cm);
+
+    while (cmp(from, coverStart.from) > 0) {
+      array.shift().clear();
+      coverStart = array[0].find();
+    }
+    if (cmp(from, coverStart.from) < 0) {
+      if (coverStart.to.line - from.line < CHUNK_SIZE) {
+        array.shift().clear();
+        coverRange(cm, from, coverStart.to, 0);
+      } else {
+        coverRange(cm, from, coverStart.from, 0);
+      }
+    }
+
+    while (cmp(to, coverEnd.to) < 0) {
+      array.pop().clear();
+      coverEnd = array[array.length - 1].find();
+    }
+    if (cmp(to, coverEnd.to) > 0) {
+      if (to.line - coverEnd.from.line < CHUNK_SIZE) {
+        array.pop().clear();
+        coverRange(cm, coverEnd.from, to);
+      } else {
+        coverRange(cm, coverEnd.to, to);
+      }
+    }
+  }
+});