The posterity is that its been mentioned in the release announcement. (flagged in unstable a while ago … so technically its been in Testing Announcements, etc too) Every release since 28 days ago.
This is a bug I just experienced on one of my manjaro computers. I was puzzled as fuck because cpu/io usage wasn’t high but it was pretty slow.
I had that happened to me using i3, the fix for me was
As stated here https://bbs.archlinux.org/viewtopic.php?id=286103