When I attempt to toggle the reader mode on the web page with the Ctrl+Alt+R shortcut the browser restarts.

It looks like the shortcut is assigned to both of the functions and the restart function takes priority.

This happens on a fresh profile.

What version of Firefox are you using? It looks like this was filed with Firefox 77, which is outdated?

Reproduced on both 77.0.1 and 79.0.

This is a developer feature from bug 1385452 that's only enabled when building Firefox locally...

The build of Firefox I use is definitely not built by Mozilla. Its built/distributed by my distribution, NixOS. But its also not a "developer" build and is intended for regular users…

Seeing the extremely low priority I don’t hold my breath of this being fixed upstream any time soon. What’s the best way to make this thing not "developer" anymore? I’ll gladly figure out how to apply it downstream and/or locally.

(In reply to Simonas Kazlauskas [:nagisa/:simukis] from comment #4)

The build of Firefox I use is definitely not built by Mozilla. Its built/distributed by my distribution, NixOS. But its also not a "developer" build and is intended for regular users…

Seeing the extremely low priority I don’t hold my breath of this being fixed upstream any time soon. What’s the best way to make this thing not "developer" anymore? I’ll gladly figure out how to apply it downstream and/or locally.

It appears that they're not building with MOZILLA_OFFICIAL=1 like other distributions do. If they fix that, that should fix this bug as far as NixOS's Firefox builds are concerned.

We (NixOS) have been building with MOZILLA_OFFICIAL=1 enabled by default since 2018/01/31.

https://github.com/NixOS/nixpkgs/commit/ce08581088897860dd3b7b510f30b093095592f3