[droidian-quirks-firefox*] Switch to software WebGL by default

[JamiKettunen]

Sandbox/seccomp appear to block libhybris from loading libGLESv2.so etc which is problematic to the point of bringing down the whole browser upon navigating to YouTube or about:support for example on Mali GPUs as seen on at least MediaTek Helio G99 (MT6789) devices.

[JamiKettunen]

Ping @g7 :) There's perhaps more testing to be done later also with HYBRIS_TLS_PATCH libhybris side but I didn't have too much luck with it so far so I'll run GPU-less FF for the time being

[JamiKettunen]

Hm afraid this actually won't work as-is, you cannot override a pref (e.g. webgl.forbid-hardware) from another file even if it should be loaded later than another one under /usr/lib/firefox/defaults/pref/*.js. Worst case I guess I'll keep it a port-specific hack but having something more generic for all other (MediaTek +) Mali GPU devices would be nice too I guess since they don't exactly make browsing the web too nice by default..