When I have two documents opened within Krita (Multiple Document Mode set to “Tab”), I noticed I can see my second document through my first document, if I lower the opacity of my background layer. See image attachments for an example of this.
I’m using Version 6.0.1 (git 9069dbc), on Windows 11.
Here are the example screens:
This is my second document.
This is my first document. You can see that I’ve lowered the opacity of the background layer and, for whatever reason, the red question mark on my second tab is showing up through it.
I tested this on an older version, and it didn’t occur.


