Comment # 4 on bug 1022830 from Felix Miata

Created attachment 713485 [details]
108 DPI Plasma screenshot comparing browsers complying or not with configured
UI fonts

In screenshot, top browser is Mozilla.org's SeaMonkey 2.47a1, next down
openSUSE's Firefox 51.0.1, next 
down Mozilla.org's Firefox ESR 45.7, bottom, Konq. ESR (built with GTK2) and
Konq obey UI font settings. GTK3 builds do not. Problem escalates rapidly as
DE's logical DPI is increased, and applies to 42.2 as well unless before
upgrading from 42.1 libgtk-3-0 is first locked down to 42.1's 3.16.7 or
installing 42.1's libgtk-3-0 in 42.2. Regression is the same in KDE3 and TDE.

Another upstream bug:
https://bugs.kde.org/show_bug.cgi?id=367499 open
usability regression: GTK+>3.16.x results in too small GTK3 app UI fonts when
logical DPI>96

Why not apply the libgtk-3-0 patch in the Gnome bug? There doesn't seem to be
any need for the patch that created the problem in the first place. As I've
seen this on Debian and Fedora too, and per the comments in the mozilla.org
bug, this is obviously not an exclusively openSUSE bug, but that shouldn't stop
openSUSE users from having the regression addressed.