Firefox freezes on startup on Wayland (but works with --kiosk or --preferences)

Problem statement I ran into a very confusing Firefox issue on Linux (Wayland): firefox → freezes / not responding firefox --kiosk → ✅ works firefox --preferences → ✅ works Creating a new tab or popup → ❌ freezes again Disabling all extensions → ❌ still freezes Creating a new Firefox profile → ✅ works Deleting prefs.js → ✅ fixes it At first glance this looks like: an extension bug GPU / cache corruption session restore issue But none of those were the real cause. ...

January 18, 2026 · 3 min · 463 words · Akhil Jalagam