This wasn't an issue before as notification popups could never have focus.
However, now with quick reply, they can, leading to funky results and gaps when a notification appears while answering another one.

5.18 please

• Ran sleep 3; notify-send foo bar and then spawned a quick reply notification and clicked the text field.

Previously I Would end up with weird situations like this, where the new notification popup would try to avoid the focussed popup, which then would also shift downwards to avoid the other popup, etc

They still avoid systray popups and the calendar as before