On Tumbleweed, many GTK apps render incorrectly when using default theme under KDE

[toomuchlinux]

I'm running Tumbleweed with KDE as my desktop. I use a lot of GTK apps and many (all?) of them have rendering problems and report errors / warnings when using the default theme. One of the simplest examples is gvim. When I run gvim, I get a number of theme-related issues reported:

(snip)
(gvim:9388): Gtk-WARNING **: Theme parsing error: gtk.css:1410:39: The :insensitive pseudo-class is deprecated. Use :disabled instead.

(gvim:9388): Gtk-WARNING **: Theme parsing error: gtk.css:1461:19: The 'icon-shadow' property has been renamed to '-gtk-icon-shadow'

(gvim:9388): Gtk-WARNING **: Theme parsing error: gtk.css:1482:19: The 'icon-shadow' property has been renamed to '-gtk-icon-shadow'

(gvim:9388): Gtk-WARNING **: Theme parsing error: gtk.css:1484:25: The '-gtk-image-effect' property has been renamed to '-gtk-icon-effect'

(gvim:9388): Gtk-WARNING **: Theme parsing error: gtk.css:1500:61: The :insensitive pseudo-class is deprecated. Use :disabled instead.

(gvim:9388): Gtk-WARNING **: Theme parsing error: gtk.css:1500:121: The :insensitive pseudo-class is deprecated. Use :disabled instead.

(gvim:9388): Gtk-WARNING **: Theme parsing error: gtk.css:1501:73: The :insensitive pseudo-class is deprecated. Use :disabled instead.

(gvim:9388): Gtk-WARNING **: Theme parsing error: gtk.css:1502:63: The :insensitive pseudo-class is deprecated. Use :disabled instead.

(gvim:9388): Gtk-WARNING **: Theme parsing error: gtk.css:1503:68: The :insensitive pseudo-class is deprecated. Use :disabled instead.

(gvim:9388): Gtk-WARNING **: Theme parsing error: gtk.css:1504:75: The :insensitive pseudo-class is deprecated. Use :disabled instead.

(gvim:9388): Gtk-WARNING **: Theme parsing error: gtk.css:1509:21: The 'icon-shadow' property has been renamed to '-gtk-icon-shadow'

(gvim:9388): Gtk-WARNING **: Theme parsing error: gtk.css:1512:63: The :insensitive pseudo-class is deprecated. Use :disabled instead.

(gvim:9388): Gtk-WARNING **: Theme parsing error: gtk.css:1512:132: The :insensitive pseudo-class is deprecated. Use :disabled instead.

(gvim:9388): Gtk-WARNING **: Theme parsing error: gtk.css:1513:75: The :insensitive pseudo-class is deprecated. Use :disabled instead.

(gvim:9388): Gtk-WARNING **: Theme parsing error: gtk.css:1514:65: The :insensitive pseudo-class is deprecated. Use :disabled instead.

(gvim:9388): Gtk-WARNING **: Theme parsing error: gtk.css:1515:70: The :insensitive pseudo-class is deprecated. Use :disabled instead.

(snip)

Also, the menus render incorrectly with no spaces at all between them:



However, when using another theme (for example, issuing GTK_THEME=Adwaita before running gvim) results in fewer errors and better looking menus.

What configuration should I look into to resolving this issue? Is this some bug with the default theme perhaps? I've not set up any other repos or manually played with any configs, so I don't think it's a conflict of any kind.

Thanks!

[wolfi323]

What configuration should I look into to resolving this issue?

Set another GTK3 theme in Configure Desktop (systemsettings5)->Application Appearance->GTK.

Is this some bug with the default theme perhaps?

Yes and no.
The problem is that the GTK3 update to 3.20 broke compatibility with themes.

And in particular KDE's default theme (breeze) has not been updated yet.