Bug 1782908 - [devtools] Turn off styleeditor transition on browser_toolbox_styleeditor.js. r=jdescottes.

The devtools-triggered transition when editing a stylesheetseems to trigger an assertion failure

Depends on D153432

Differential Revision: https://phabricator.services.mozilla.com/D153722

devtools/client/styleeditor/test/browser_toolbox_styleeditor.js

@@ -23,6 +23,8 @@ Services.scriptloader.loadSubScript(
 );
 
 add_task(async function() {
+  await pushPref("devtools.browsertoolbox.scope", "everything");
+  await pushPref("devtools.styleeditor.transitions", false);
   await addTab(TEST_URI);
   await pushPref("devtools.browsertoolbox.scope", "everything");
   const ToolboxTask = await initBrowserToolboxTask({