User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_4) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/13.1 Safari/605.1.15

Steps to reproduce:

1. In Windows, enable the dark app theme.
2. Install Dark Reader addon
3. Enable Dark Reader
4. In Dark Reader settings change theme generation to Custom.
5. Restart Firefox
6. Go to about:home

Actual results:

The page is white

Expected results:

Page should be dark

Hello,

I’ve managed to reproduce the issue as per the provided STR on the latest Nightly (81.0a1/20200812214948), Beta (80.0b7/20200811133449) and Release (79.0/20200720193547) under Windows 10 Pro 64-bit.

I have also attempted to provide a regression window for the issue by running a bisection from 2018-08-01 until the present day. Results show that this has always been the case since the introduction of the dark color scheme via OS settings. I’ve also noticed that this issue also occurred when manually applying the default dark theme of the browser and then proceeding with the STR.