1 files changed, 64 insertions, 0 deletions
diff --git a/browser/extensions/screenshots/clipboard.js b/browser/extensions/screenshots/clipboard.js
new file mode 100644
index 0000000000..d4dbc38a14
--- /dev/null
+++ b/browser/extensions/screenshots/clipboard.js
@@ -0,0 +1,64 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/* globals catcher, assertIsBlankDocument, browser */
+
+"use strict";
+
+this.clipboard = (function () {
+  const exports = {};
+
+  exports.copy = function (text) {
+    return new Promise((resolve, reject) => {
+      const element = document.createElement("iframe");
+      element.src = browser.runtime.getURL("blank.html");
+      // We can't actually hide the iframe while copying, but we can make
+      // it close to invisible:
+      element.style.opacity = "0";
+      element.style.width = "1px";
+      element.style.height = "1px";
+      element.style.display = "block";
+      element.addEventListener(
+        "load",
+        catcher.watchFunction(() => {
+          try {
+            const doc = element.contentDocument;
+            assertIsBlankDocument(doc);
+            const el = doc.createElement("textarea");
+            doc.body.appendChild(el);
+            el.value = text;
+            if (!text) {
+              const exc = new Error("Clipboard copy given empty text");
+              exc.noPopup = true;
+              catcher.unhandled(exc);
+            }
+            el.select();
+            if (doc.activeElement !== el) {
+              const unhandledTag = doc.activeElement
+                ? doc.activeElement.tagName
+                : "No active element";
+              const exc = new Error("Clipboard el.select failed");
+              exc.activeElement = unhandledTag;
+              exc.noPopup = true;
+              catcher.unhandled(exc);
+            }
+            const copied = doc.execCommand("copy");
+            if (!copied) {
+              catcher.unhandled(new Error("Clipboard copy failed"));
+            }
+            el.remove();
+            resolve(copied);
+          } finally {
+            element.remove();
+          }
+        }),
+        { once: true }
+      );
+      document.body.appendChild(element);
+    });
+  };
+
+  return exports;
+})();
+null;