@coderus: Thanks a lot!
Quickly checking Patchmanager’s basic functions (especially those reported to be broken), it seems to work fine (RPM for armv7hl from CI on an XperiaXA2+@SFOS4.0.1).
P.S.: I was not aware (until downloading and installing its current artefact, triggered by your notice), that you have a CI pipeline running for Patchmanager at Github: nice!
P.P.S. (reading the comments below): I had all patches unapplied before upgrading SailfishOS!
P.P.P.S.: See my addendum.