1585091 - Setting gfx.webrender.all=false does not disable WebRender

Status: RESOLVED WONTFIX

(Core :: Graphics: WebRender, defect, P5)

Description

[Botond Ballo [:botond]]

STR

1. Build Firefox locally. Presumably to repro this, you need to be on a machine where WR is enabled by default.
2. Run mach run --setpref gfx.webrender.all=false

Expected results

Firefox runs with WebRender disabled.

Actual results

Firefox runs with WebRender enabled. If I go to about:config, gfx.webrender.all is set to false. If I close Firefox and run the same command again, WebRender is still enabled.

Comment 1

[Botond Ballo [:botond]]

It sounds like I need gfx.webrender.force-disabled=true?

I find it pretty counterintuitive that gfx.webrender.all=true works when disabled is the default, but gfx.webrender.all=false does not work when enabled is the default.

Comment 2

[Darkspirit]

gfx.webrender.all == set all required prefs: enable WR and on Linux also force-enable OpenGL layers
gfx.webrender.all.qualified (hidden pref) == enable WR by default on qualified systems
gfx.webrender.enabled == enable WR (won't work on Linux unless layers.acceleration.force-enabled is set to true)
gfx.webrender.force-disabled == force-disable

So you can either set gfx.webrender.all.qualified=false (hidden pref) or gfx.webrender.force-disabled=true.