Dolphin and KDE settings no longer blur transparent windows

Hi, recently I updated to plasma 6. Everything is awesome so far except the fact that I’ve lost my “frosted glass” effect on some windows like Dolphin, using Kvantum I’d make it transparent and it would blur the windows in the background giving it a frosted glass effect, it does it correctly in Kvantum but everything else it does not. I tried messing with the Desktop effect of Blur and that still doesn’t fix it.
Screenshot for reference, Konsole still has this feature but other windows lack it.

As far as I understand, the “Blur” desktop effect in system settings controls how kwin blurs the transparent sections of windows that have areas with alpha channel (such as Konsole with a transparent background), but it does not blur behind windows that are themselves in their entirety made semi-transparent by kwin itself.

See 392693 – [wayland] - Blur effect isnt applied under wayland

So would this be considered a Kwin issue then? That’s what I would imagine with what I’m getting. Oddly enough that link you sent has someone who’s experiencing the same issue I am and not from long ago.

It’s a combination of 392693 – [wayland] - Blur effect isnt applied under wayland and 480608 – Windows are not transparent with transparent colors with Breeze theme.

I just wanted to mention that I’m having the same happen on the Fedora 40 Plasma Prerelease, since I saw that it was marked resolved/fixed. I’m not sure if it’s been pushed out yet via update.

Everything except kvantum, even with blur enabled, is completely unresponsive to any blur settings, and it just shifts to being, in my case, a combination of tinted and virtually completely transparent, despite the effect still applying to kvantum-manager as well as the plasma theme / panels.

This is actually a Kvantum issue. If you look on their GitHub they said that it’s an issue with Kwin i believe. 1.10 should fix it hopefully.

That makes sense actually. I appreciate the response on it!

On an off note, is the transparency slider in Breeze, under application style, actually supposed to do anything at the moment, or is it just a placeholder? I ask because it doesn’t seem to have any effect on Dolphin, Kate, etc (in my case).


I should not that the transparency slider affects the context menu, but not actually any of the applications, that I can tell.

For me it also does nothing, but that is probably because of Kvantum. Try and see if it does anything without any Kvantum themes?