For Android users seeking a privacy-focused browser, Privacy Guides recommends Mull:
Mull is a privacy oriented and deblobbed Android browser based on Firefox. Compared to Firefox, it offers much greater fingerprinting protection out of the box, and disables JavaScript Just-in-Time (JIT) compilation for enhanced security. It also removes all proprietary elements from Firefox, such as replacing Google Play Services references.
Mull enables many features upstreamed by the Tor uplift project using preferences from Arkenfox. Proprietary blobs are removed from Mozilla’s code using the scripts developed for Fennec F-Droid.
You can’t do that in about:config?