[krono]

There is chrome://geckoview/content/config.xhtml but many options shown there are nonfunctional. The relevant option is listed but I'm not sure if setting it to false has any effect.

Edit: Just found out that on that link above, you can set general.aboutConfig.enable to true to enable about.config.

It looks like the xml page and the about.config one are the same, as the modifications I made are synced.

[neitsab]

Thank you so much for that! I was missing the ability to configure a very important option for me in Stable (layout.css.prefers-color-scheme.content-override), but couldn't keep using Nightly because of its instability... You're a lifesaver!