1 files changed, 28 insertions, 0 deletions
diff --git a/devtools/shared/commands/resource/legacy-listeners/css-changes.js b/devtools/shared/commands/resource/legacy-listeners/css-changes.js
new file mode 100644
index 0000000000..e9f3e17075
--- /dev/null
+++ b/devtools/shared/commands/resource/legacy-listeners/css-changes.js
@@ -0,0 +1,28 @@
+/* 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/. */
+
+"use strict";
+
+const ResourceCommand = require("resource://devtools/shared/commands/resource/resource-command.js");
+
+module.exports = async function ({ targetFront, onAvailable }) {
+  if (!targetFront.hasActor("changes")) {
+    return;
+  }
+
+  const changesFront = await targetFront.getFront("changes");
+
+  // Get all changes collected up to this point by the ChangesActor on the server,
+  // then fire each change as "add-change".
+  const changes = await changesFront.allChanges();
+  await onAvailable(changes.map(change => toResource(change)));
+
+  changesFront.on("add-change", change => onAvailable([toResource(change)]));
+};
+
+function toResource(change) {
+  return Object.assign(change, {
+    resourceType: ResourceCommand.TYPES.CSS_CHANGE,
+  });
+}