Optimize Firefox on Fedora/Linux for performance and stability ("no glitches, but holds up"): about:config tweaks via user.js (Betterfox/Fastfox verified list), hardware acceleration, WebRender check, uBlock Origin, profile location gotchas, slow-video diagnosis (VA-API/NVIDIA, Flatpak GOTCHA). Use when the user asks to speed up Firefox, fix browser glitches/lag/video freezes/stuttering streams, or apply Firefox performance tweaks.
