This change to Cargo:
https://gerrit.wikimedia.org/r/c/mediawiki/extensions/Cargo/+/901699
...seems to be causing all Page Forms patches to fail validation. See here:
https://gerrit.wikimedia.org/r/c/mediawiki/extensions/PageForms/+/902732
The issue seems to be that Cargo now defines stub versions of various Admin Links classes (ALSection, ALRow, etc.) - and Page Forms' validation is getting confused by the fact that each of these classes is now defined in two different places.
I'm sure there are workarounds to this - but does Cargo really need to re-declare these classes? I don't know of any other extensions that do that.