It's cute that we have
on the server, however it's never loaded and hence ignored.
is loaded, so the whole setup is busted.
I realized by trying to sync our code with https://projects.kde.org/projects/websites/bugs-kde-org/repository/changes/weekly-bug-summary.cgi?rev=kde and trying to test it on boogs.wmflabs.org, where clicking "Links > Weekly Summary" in the sidebar triggers a 404. Only after copying it to the root directory via
mv extensions/WeeklyReport/weekly-bug-summary.cgi .
and running ./checksetup.pl it works.