Thank you! I was able to fix this.
(It was somehow related to Java Script text transformers, maybe you configured one previously and BTT mistakenly didn't correctly update the action after you removed it again). This should now be resolved in 3.756!
Funny that you mention Javascript Transformation, because for me it calls my JavaScript Transformation on the clipboard item, even though I want to paste as one line.
This is my configuration, QR Code is my JS Transformation, which I use from the clipboard manager but dont want here, yet it is called when I use the shortcut.