1900710 - Brief bright flash of blank/white background color, when opening new tab with wallpaper

Status: NEW

(Firefox :: New Tab Page, defect, P3)

Description

[Daniel Holbert [:dholbert]]

STR:

1. In about:config, set browser.newtabpage.activity-stream.newtabWallpapers.enabled to true
2. Open a new tab, tap the cog icon, and choose the top-right option (yellow/pink/blue swooshes), or any one that's darker than our default white tab-background.
3. Open a new tab.
4. Open another new tab. (Repeat as-needed.)

ACTUAL RESULTS:
When the new-tab opens, there's a brief flash of the blank page background (which is much brighter than my selected tab wallpaper). This can be a pretty disconcerting flicker, if there's a substantial brightness difference and if you open several new tabs in a row.

EXPECTED RESULTS:
No such flash of the blank new-tab background-color.

Comment 1

[Daniel Holbert [:dholbert]]

Here's a profile showing the issue -- notice the blank rendering in the screenshots track from 2.52s to 2.60s:
https://share.firefox.dev/3KzgOdK

Comment 2

[Daniel Holbert [:dholbert]]

You can also see the blank rendering while we load the new-tab in the screencast that I just posted on related bug 1900711, at around t=1s.

Screencast: https://bug1900711.bmoattachments.org/attachment.cgi?id=9405598

Comment 3

[Timothy Nikkel (:tnikkel)]

Possibly an instance of bug 1556156. If you use a wallpaper that reports itself as containing transparency (even if it doesn't) and the problem goes away that would be good evidence of that. Using a png with rgba (instead of just rgb) color should be enough for that. The pngcheck command line program can be used to check.