When adding or removing a page from a group on [[m:Special:AggregateGroups]], the change is saved (as I can check by refreshing the page), but I get the error "Exception Caught: Error in numRows(): Table 'metawiki.revtag_type' doesn't exist (10.0.6.36)" which is a bit ugly at least.
Another error with revtag_type was bug 39287, provisionally adding it in dependencies.
Version: 1.21.x
Severity: major
URL: https://meta.wikimedia.org/wiki/Special:AggregateGroups