Hi,

while using the profiler, I noticed recently that the marker chart is blurry in some occasions, but not always.

On my computer, I can reproduce with these steps:

1. Load this profile: https://share.firefox.dev/3ZnfkcE
2. Look approximately in the center of the line, next to the end of PBrowser::Msg_Destroy: we clearly see that the rectangle marker isn't aligned with the small marker that is just a vertical line.

When zooming in in the profiler (not the page zoom) with the ctrl + mousewheel on the marker chart, we clearly see that at some zoom level the rectangle is drawn more precisely.

This is the code that draws the rectangles:
https://github.com/firefox-devtools/profiler/blob/bfcbd6ea0e44dc4c3d83bdea5115f80a20702286/src/components/marker-chart/Canvas.js#L306-L320

This is the code that draws the thin line:
https://github.com/firefox-devtools/profiler/blob/bfcbd6ea0e44dc4c3d83bdea5115f80a20702286/src/components/marker-chart/Canvas.js#L298

I'm using X11 on Linux.

stable 110 doesn't have the problem on my machine.
However I tried to run mozregression and I see the problem when specifying v110 and it's downloading a nightly version of it. Then it could be a pref difference ?

Comment 1 makes it sound like this is a problem with accelerated canvas2d, which was enabled for a while in Nightly before shipping in 110 (bug 1806058). Are you able to reproduce when gfx.canvas.accelerated is disabled in about:config?

Indeed I don't reproduce when it's disabled.

Set release status flags based on info from the regressing bug 1770088

:lsalzman, since you are the author of the regressor, bug 1770088, could you take a look? Also, could you set the severity field?

For more information, please visit auto_nag documentation.

Set release status flags based on info from the regressing bug 1770088

:julienw do you still can reproduce this?

Hey Suhaib,
yes I can still see this in v113 20230328095108.

Here is a screenshot of the issue...

Thanks!