It is definately two different problems. The bubbles can't be less blur than
they are in the exemple files shown by Mirco at the end of the bug report I
posted in my previous comment.
About your icons not appearing when they are not square, I am not sure if it
is the actual issue. I remember some album art not working in Exaile with a
development version of notify-osd, but the issue vanished without me being
able to find how to reproduce it.
It is definately two different problems. The bubbles can't be less blur than
they are in the exemple files shown by Mirco at the end of the bug report I
posted in my previous comment.
About your icons not appearing when they are not square, I am not sure if it
is the actual issue. I remember some album art not working in Exaile with a
development version of notify-osd, but the issue vanished without me being
able to find how to reproduce it.