Because of the following exception: getCachedMessages: TypeError: this.window.performance is undefined\nStack: WCA_onGetCachedMessages@resource://gre/modules/commonjs/toolkit/loader.js -> file:///mnt/desktop/gecko/devtools//server/actors/webconsole.js:741

It seems to be also broken for the browser content toolbox.

Comment on attachment 8691396 [details] [diff] [review] patch v1 Review of attachment 8691396 [details] [diff] [review]: ----------------------------------------------------------------- Please update commit message to describe the fix - maybe 'Fix the webconsole for addon and browser content toolbox by handling a missing performance property on this.window'. ::: devtools/server/actors/webconsole.js @@ +736,5 @@ > if (!this.consoleAPIListener) { > break; > } > > + let requestStartTime = this.window && this.window.performance ? So I checked into this for Browser Content Toolbox and it seems that this.window is coming from this._consoleScope on the ChildProcessActor which is a Sandbox. I'm assuming that's the same setup when debugging addons. Can you add a comment above this condition explaining that this.window can be a Sandbox in Addon or Browser Content Toolbox?

[Tracking Requested - why for this release]: This is a regression from Bug 1222617 and should go to aurora along with that bug if/when it gets uplifted

Feel free to review the comment I added.

https://hg.mozilla.org/integration/fx-team/rev/f516533b96a46764f288d336415e5a8aa3468e21 Bug 1227139 - Fix the webconsole for addon and browser content toolbox by handling a missing performance property on this.window. r=bgrins

Comment on attachment 8691425 [details] [diff] [review] patch v2 Approval Request Comment [Feature/regressing bug #]: 1222617 [User impact if declined]: Browser Content Toolbox / Addon Toolbox console won't retrieve cached messages (chrome debugging only) [Describe test coverage new/current, TreeHerder]: No new coverage.. These special toolbox processes don't have any test coverage AFAIK [Risks and why]: Limited risk. This is only changing behavior for these special chrome debugging cases, and it's a trivial change that adds an extra check on a property before accessing it. [String/UUID change made/needed]:

Tracked since it's a regression that occurred in FF44.

Comment on attachment 8691425 [details] [diff] [review] patch v2 This patch fixes a regression and has been on nightly for a few days, seems safe to uplift to Aurora44.