I recently started seeing many FOUCs on different websites, especially https://github.com.
Without realizing the issue was caused by Firenvim, I used Stylebot and Violentmonkey to hide the FOUCs.
After several unsuccessful attempts, I started disabling different addons to see if they were causing this behavior. After many rounds of testing, I found Firenvim to be the culprit.
Do you think I can do anything to prevent the FOUCs when Firenvim is enabled?
Huh, I had never noticed this, but I can reproduce what you're describing on Github when performing a hard reload. I'll investigate, thanks for the report.
Description
Do you think I can do anything to prevent the FOUCs when Firenvim is enabled?