Blur in the window title is broken

[MoarcyVega]

Hello,
at first: I love your Sweet KDE Theme.
After the Update to KDE 5.25 they changed something to handle the blur effect in window titles. I read on reddit that themes must be fixed to get it working again.
i read it here: https://www.reddit.com/r/kde/comments/vgohjs/why_are_my_title_bars_not_getting_blurred_i_tried/
Is there any way you could fix or update Sweet KDE or can you tell me how i could fix it by myself so blur on the window title works again?

Thank you a lot :)

[kawazoe]

Relevant KDE bug thread: https://bugs.kde.org/show_bug.cgi?id=395725#c85

EDIT: Potential reference implementation from ClassiK paulmcauley/klassy@fe48c05