Canvas glitching on: Undo, switching tabs, using eraser

[bitbof]

1) The issue

Since the end of January 2022 many reports have come in of Kleki glitching after switching tabs. All of them appear to come from ChromeOS/Chromebook users. Glitching occurs after pressing Undo, switching tabs, zooming, or when using the eraser. Glitching includes:

• Parts of layers getting "erased"
• Layers getting "pixelated"
• Corners around brushstrokes getting erased
• Drawing turning gray

3) More details

Example of the glitch (from here)

And another

Note the blocky erased sections.

After buying two different Chromebooks I was finally to reproduce it myself. I created a page that provokes the Chrome glitch: https://bitbof.com/stuff/2022-04-28-intelhd400-canvas/
It is not an issue with Kleki, but Chrome.

4) Chromium Report

A Chromium issue has been created on Mar 24, 2022

https://bugs.chromium.org/p/chromium/issues/detail?id=1309876#c_ts1648128675

[motheye]

I have been experiencing this too, altho I think it is just when I undo or switch tabs and then draw. I have an Acer Chromebook 14 CB3-431 and I use a one by wacom drawing tablet. Here are some examples:

It has been happening almost every time I switch tabs or undo.
I apologize if this was unhelpful, or an improper way to report the bug. I am unaware of any other way to report it.

[bitbof]

@motheye motheye Thanks for reporting and your screenshots. Would it be possible for you to create a screen recording of the bug in action? From when things are fine, to it starting to glitch, and what it looks like to continue drawing.

[motheye]

I would but it just stopped happening. If it happens again, I will try and record it. I just noticed the feedback option at the bottom of the screen, would you like me to contact you that way in the future?

[bitbof]

Many thanks!
Either way is fine 👍 and contact@kleki.com works too.

[motheye]

Here is a video of the glitch happening when I switch tabs, I will try and get a video of the undo glitch as well. https://watch.screencastify.com/v/jPajhz7TB0ecjZABdkYZ
I was not using the drawing tablet in this recording.

[bitbof]

@motheye Fantastic! Super helpful and interesting. Makes it clear that this is very likely an issue with Chrome itself.

I will try to build a simplified page that provokes the same issue, for a Chrome (chromium) bug report.

[motheye]

Thank you, and good luck!

[bitbof]

@motheye Hi again, I am in the process of drafting a bug report. Would you grant me permission to share your video with Chrome developers in a Chromium Bug report? It is possible for anyone to view such a report. Your name will not be mentioned and I will censor everything that is not relevant to this bug.

[bitbof]

Received an Acer Chromebook CB3-431, and I can finally reproduce this elusive bug! Time to celebrate!

[bitbof]

Interestingly this also affects ChickenPaint

[motheye]

I am so sorry for not responding for so long. Yes, you can share the video, altho it may not be relevant now. You have my congratulations for getting an Acer Chromebook and my thanks.

[bitbof]

@motheye Yea the video is not needed anymore. No worries!

[CodiBAsh]

With the "tab switching" causes bug I found that if you hit undo sometimes it fixes it but i have not yet come across the problem when hitting undo .

[motheye]

I have not come across any problems for a few months now.

…

On Thu, Jan 5, 2023 at 2:24 PM CodiBAsh ***@***.***> wrote: With the "tab switching" causes bug I found that if you hit undo sometimes it fixes it but i have not yet come across the problem when hitting undo . — Reply to this email directly, view it on GitHub <#2 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AYFMGUC56SJ2PXWWRRWLELDWQ4NYLANCNFSM5PATTX3A> . You are receiving this because you were mentioned.Message ID: ***@***.***>

[CodiBAsh]

Perhaps it's a thing that was fixed with a new update to the chrome OS because i haven't used chrome for a while now and chrome updates a lot .