Bug#843104: firefox: Things that are still bad with GTK+3 enabled

[Jeff King]

On Thu, Nov 03, 2016 at 09:18:15PM -0400, Matthew Gabeler-Lee wrote:

> I do run GNOME, and it works fine on my HiDPI screen there.
> 
> Do you have some value set for layout.css.devPixelsPerPx, or is it the
> default -1?

I do have it set, though restoring it to "-1.0" does not change anything
with the widgets (it just makes the rendered content look really tiny,
too). Interestingly, GTK2 sizes things reasonably even with "-1.0" (many
versions back I set it manually, but apparently that is no longer
necessary). So it seems like GTK2 figures out the DPI issues
automatically, but GTK3 does not.

> > I don't run GNOME, but I do have "dconf" installed. Tweaking
> > "/org/gnome/desktop/interface/scaling-factor" (and text-scaling-factor)
> > has no effect.
> 
> In my GNOME environment, the first is 0 and the second is 1, and yet I get
> proper sized stuff in HiDPI nonetheless.
> 
> However, the gnome-tweak-tool shows the "Window scaling" as 2.

Thanks for the input. I tried installing gnome-tweak-tool, but changing
the settings had no effect (I imagine this is because I'm not running
some other component, like the compositing window manager, that does the
heavy lifting).

I opened #843104 to to split this issue into its own bug.

-Peff