yuli@,
Could you help find the culprit of the regression?
I tried it on kevin and it's reproducible.

I have reproduced the problem in CrOS camera app on chromebooks: the effects' canvas in the toolbar flickers when the mouse hovers on/off a button; it might be related to recent canvas rendering changes (crbug.com/788439#c7)?

I have verified it didn't flicker on Chrome 65.0.3294.0/10215.0.0 and could reproduce the flickering issue on Chrome 65.0.3295.0/10217.0.0.

junov@, would you please help to take a look? Thanks much.

@yuli: I'm not currently set-up for ChromeOS development, before go through all the setup steps, could you check whether the issue is still reproducible in the latest build?

I suspect this might be a duplicate of  issue 795635  which was fixed by this CL:
https://chromium.googlesource.com/chromium/src/+/c1fd548f2cf9a3585e82d800cfc40167a48bb582

That bug was reported as mac-specific, but the code path that had the bug is also used on CrOS.

The issue is reproducible on ChromeOS with the latest build: Chrome 65.0.3316.0/10298.0.0.

Okay Thanks.  I'll take it.

Any update on this? 

It is marked as a beta blocker for 65, and the beta promotion date is only a week away.

We need to promote to beta soon, is there any chance we can get this fixed in the next couple days?

Considering the impact here, and the impending beta, I think we can punt this to a stable blocker to buy some more time.

No repro on ToT. (FYI: My dev device is a kevin)

There are a number of canvas rendering glitches that were fixed in the last week, all of which have already been merged to M65.

Need confirmation that this is fixed in latest 66 and 65 builds. 

Note: Some of the merges to 65 happened earlier today, so they are not in the latest dev channel release. Confirmation needs to be done against a build later than commit position 298 on the 3325 branch.

Hi Justin. Is there a test that can catch bugs like this in the future?

@#15: Currently there is not.  As a part of an upcoming post mortem, I intend to study how this can be achieved.

In the past, I have added tests to third_party/WebKit/ManualTests for flickering issues, but those tests never get run.  We need to come up with an automated way of detecting flickering (or of detecting the race conditions that cause flickering)

Marking as WontFix due to no repro.

Issue still needs verification since I don't have access to the exact same hardware this was originally reported against (I'm in a remote office).