1922995 - Image of error page is flashing white on reload in dark mode

Status: NEW

(Firefox for Android :: Browser Engine, defect, P3)

Description

[Manuel Bucher [:manuel]]

Attachment: screen-20241007-075436.mp4

Steps to reproduce

1. have dark mode enabled
2. Have no internet connection
3. Reload connection error page

Expected behavior

No white flashing of image

Actual behavior

Device information

• Firefox version: Android 132a1 2024-09-03
• Android device model:
• Android OS version:

Any additional information?

Comment 1

[BugBot [:suhaib / :marco]]

The severity field is not set for this bug.
:amejia, could you have a look please?

For more information, please visit BugBot documentation.

Comment 2

[Lukasz Gniadzik [:lgniadzik]]

Attachment: Bug 1922995 - Hide image on the error page until it is fully loaded. r=#android-reviewers,#frontend-codestyle-reviewers

Comment 3

[Lukasz Gniadzik [:lgniadzik]]

The reported problem was caused by not hiding the errorImag while it was still loading. This can be solved by initially setting its visibility to hidden and then updating it in the onload callback function to make it visible.

It's worth mentioning that this problem should also be observed on other error pages (for low, medium, and high error risks) because a single HTML file is reused for low and medium risk errors, while high-risk errors are handled by a different HTML file:

• low and medium risk errors -> low_and_medium_risk_error_pages.html/css/js
• high-risk errors -> high_risk_error_pages.html/css/js.

Attached change only addresses issue for low and medium risk errors.

Comment 4

[Polly [:polly]]

Attachment: intermittent flashing observed with the patch

hello and thank you for your contribution - we appreciate you sending us a patch! :raised_hands:

a couple of things we noticed when looking at this:

a) the design for the error pages has recently changed (the new page is centred and has a picture of a fox)
so any changes made to the previous page would need reapplying to this new design.

b) with the old design and your patch, i am still seeing some flickering of the white background behind the image. it's not happening every time, but definitely visible intermittently. i've attached a video of what i am seeing (from samsung galaxy s24, android 14).

if you are planning on working on this further, i suggest you rebase locally, or re-checkout the default branch to get the latest code first.
The flicker is still happening on the new design unfortunately. If you can manage to stop the flicker entirely for the new design, that would be amazing! But it's also very helpful just to let us know about this issue, so thanks for reporting it!

Comment 5

[BugBot (nomail) [:suhaib / :marco/ :calixte]]

The bug assignee is inactive on Bugzilla, so the assignee is being reset.

Comment 6

[BugBot [:suhaib / :marco]]

The Bugbug bot thinks this bug should belong to the 'Fenix::Browser Engine' component, and is moving the bug to that component. Please correct in case you think the bot is wrong.