Blur not working in GTK apps in latest version

[giohessel]

Hyprland version

0.56.2

Is this a regression?

yes, used to work at least before the last system update, october 7th

What's the bug?

so, after a full system upgrade, in which GTK 4 apparently received some sort of meaningful update, blur does not work for any GTK apps.

i first noticed it after installing nicotine+, but apparently all GTK apps are suffering from this. i tested nautilus, swayNC, nicotine, and pavucontrol. curiously, the file picker dialogs from xdg-desktop-portal-gtk blur just fine.

i have already rebooted the system (twice), reviewed my hyprland config, checked the syntax for that, switched to the stock GTK theme instead of my custom one, and spent a lot of time trying to troubleshoot with AI, but nothing seems to work...

Reproduction steps

1. GTK 4 version 4.24.1, GTK 3 version 3.24.52-2, hyprland 0.56.2
2. enable global blur and some level of window transparency
3. open any GTK app such as nautilus
4. window does not blur

Attachments

sysinfo:

systeminfo.txt

relevant hyprland configs:

config.txt

pacman log for last update:

(and all changes up until the point i noticed the bug)
pacman-log.txt

I acknowledge that:

• I have searched all (open and closed) discussions and issues and my problem is not there.

• I have read the Code of Conduct and agree to follow it.

• I wrote this request with my own hands, my own keyboard, and in my own words.

[aashish254]

first isolate: does blur still work on non-gtk apps (qt, terminal)? if yes, its gtk-specific, not a global blur break — that narrows it a lot.

gtk4's renderer choice affects how hyprland's blur hooks in. try GSK_RENDERER=gl hyprland-app on one of the broken gtk apps and see if blur comes back — if it does, the regression is in the renderer path, and pinning the renderer is your workaround until its fixed upstream.

also search the hyprland issue tracker for 0.56.2 blur reports — regressions like this usually get bisected fast and someones already posted a workaround. report back what the GSK_RENDERER test shows and its much easier to pin down.

[wabarTM]

https://gitlab.gnome.org/GNOME/gtk/-/merge_requests/10145#note_2813868

[Dregu]

I'll just clear this up a bit. This is how this protocol is designed to work. The client sets a background effect and tells which region should be blurred. GTK has chosen to turn blur off by default in the whole toolkit. Windows aren't even transparent by default, how could they be blurred by default. (Kinda like foot turned it off by default, for which we got a hundred "bug" reports last time.) The theme that makes your windows transparent can also make them blurred.

A minimal gtk theme with transparent and blurred background could look like this, how the gnomes intended:

/*   ~/.config/gtk-4.0/gtk.css   */
window {
    background-color: rgba(40, 40, 40, 0.8);
    backdrop-filter: blur(20px);
}

"I just want the old way back." You can also set the env GDK_WAYLAND_DISABLE=ext_background_effect_manager_v1 and gtk won't use the protocol at all, just like the old version. Whole ass toolkits disabling blur by default kinda begs the question should Hyprland have a rule to force blur on windows that specifically wanted to disable it, and I guess the answer is yes, but that doesn't currently exist.

[alba4k]

uhm, that doesn't seem to re-enable blur in swaync for me though? on the other hand, the env works, so I'll probably just set-and-forget that

[giohessel]

combining both the backdrop-filter setting and the env variable worked flawlessly. tysm for the answer!

[shayanmoosavi]

Typical GNOME being GNOME. Disabling that protocol solved the blur not applying. Another reason why I hate GNOME and will never ever use it. Thanks for the answer!

[khalid151]

@alba4k for swaync to work, you have to set it in its CSS as it overrides\ignores GTK themes by default.

Try this, for example

.control-center, .floating-notifications {
  backdrop-filter: blur(20px);
}

[gfhdhytghd]

Add a force_hl_bg_effect maybe?
Don't know if it's a good idea