User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:84.0) Gecko/20100101 Firefox/84.0

Steps to reproduce:

Restarted my PC
Launched Firefox (Firefox Alpenglow Dark Enabled)

Actual results:

About:home is white or follows the light theme even though dark theme is enabled.
But if I open a new tab, the theme followed by that tab is dark.
Then the first tab switches to dark
I have noticed this issue many times.

Expected results:

about:home should follow dark theme on startup of Firefox.

Hi,

I wasn't able to reproduce your issue on Firefox 84 or Firefox Nightly 85.0a1

Could you check if this also occurs in safe-mode?
Here is a link that can help you with that:
https://support.mozilla.org/en-US/kb/troubleshoot-firefox-issues-using-safe-mode#w_how-to-start-firefox-in-safe-mode

Thanks!

Bugbug thinks this bug should belong to this component, but please revert this change in case of error.

(In reply to Peter_M from comment #1)

Hi,

I wasn't able to reproduce your issue on Firefox 84 or Firefox Nightly 85.0a1

Could you check if this also occurs in safe-mode?
Here is a link that can help you with that:
https://support.mozilla.org/en-US/kb/troubleshoot-firefox-issues-using-safe-mode#w_how-to-start-firefox-in-safe-mode

Thanks!
The problem still occurs in Safe Mode.
Sorry but I really don't know how to explain this technically. I think 'regression' is a great term to describe this problem. Sometimes the new tab page will actually flash white quickly. I did face a similar issue earlier, that's a little different from the current issue.
(link: https://bugzilla.mozilla.org/show_bug.cgi?id=1653505)
Thank you!