Open Bug 1726998 Opened 3 years ago Updated 8 months ago

Text characters get garbled randomly

Categories

(Core :: Graphics: WebRender, defect, P3)

Unspecified
Android
defect

Tracking

()

People

(Reporter: amoya, Unassigned)

References

(Blocks 2 open bugs)

Details

Attachments

(2 files)

From github: https://github.com/mozilla-mobile/fenix/issues/19851.

On Firefox for Android on my Pixel 5 phone, when I'm viewing a web page, often the text characters are rendered incorrectly. For example some characters get missing or misplaced. I cannot find a pattern for when this happens but it's quiet often and is more likely to happen on pages with dense text content.
The problem goes away as I do an action that refreshes the text, like changing the zoom, but can happen again on the same page after a few seconds.
I have had this problem for as long as I remember (at least 6 months) and it's still there on the latest version of Firefox that I'm using.

Build info:
89.1.1 (Build #2015812947)
AC: 75.0.22, 5204f4025
GV: 89.0-20210527174632
AS: 74.0.1
Phone: Pixel 5

I have attached a few screen shots to show the problem, but I can provide more if needed.

Change performed by the Move to Bugzilla add-on.

Seems like more likely to be graphics-related.

Component: Layout → Graphics: WebRender

From the screenshots it look like there's usually a single letter (but a different letter in each screenshot, though) which is rendered at an incorrect offset. Which makes me think the offset is getting corrupted reasonably early in the pipeline, perhaps when loading the font.

I can provide reproducibility details, screenshots or even screen recording to help move forward on fixing this bug. This may not be a widespread issue but is immensely affecting usability of the app. So I'm happy to help resolve it sooner.

Thanks Amir. A few questions then:

  • What device do you have?
  • What websites does this happen on? Only a few specific websites or most of the ones you visit. Please give a couple of common examples if it's most websites.
  • How frequently does it occur? eg Once a day, or basically every time you open a web site?
  • Have you changed any font settings, either in Firefox or the android system settings?

A screen recording would be very helpful, thanks!

Also, if you could try installing Firefox Nightly, then go to about:config, set gfx.webrender.software to true, and restart Firefox Nightly. Can you then reproduce the issue in Nightly?

Flags: needinfo?(amir.khosroshahi)

Hey Jamie,

I also installed Firefox Nightly and set gfx.webrender.software to true in about:config, but was able to notice the issue again.

Flags: needinfo?(amir.khosroshahi)

Thanks Amir. Could you please go to about:support, click on "Copy text to clipboard", and attach the information to this bug? Thanks.

Flags: needinfo?(amir.khosroshahi)
Flags: needinfo?(amir.khosroshahi)

Here you go Jamie. I attached the info you requested to this bug.

Blocks: wr-android
Severity: -- → S3
Priority: -- → P3

Hello. Is this bug still in the queue to be addressed? I'm still having this issue as of Firefox 98.3.0 on Pixel 5

Appears also with Thunderbird 102.2.1 .
Before characters were only missing. Now characters are also garbled.

So far best case for recreation is the custom print-dialog: simply try to print an attached document, e.g. PDF.

Update: Thunderbird 102.2.2 fixes most(!) of the problems.
A few issues still occur (on bottom of the print-dialog, after scrolling down)

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