I've recently been battling a painful bug on http://practicalplants.org, whereby all Cite <refs> were left as unsubstituted UNIQ…QINU tags for anonymous users, when anonymous editing is disabled, and additionally a "You do not have permission to edit this page" message was output at the top a number of times, when viewing the page. The bug is not present if the page is rendered by an authenticated user.
In going through bug reports it seems this can be triggered by a pretty wide range of problems, most of which are reported as resolved, eg https://bugzilla.wikimedia.org/show_bug.cgi?id=14959
Through very slow delete-save-does-it-work-yet debugging I finally hunted it down to a small typo in a template - {{#arrayap…}} instead of {{#arraymap…}}) - and oddly to assigning a comma separated list to the SMW property. I have no clue why either of these things should cause such behaviour.
Anyway, I'm curious if anyone has any experience with the internals behind this bug (or bugs?), and could give me some a starting point to begin digging around and see if I can find a way to ouput a useful error message or something. Also, if anyone has any idea why this only affects anonymous users when anonymous editing is disabled, that might help me find a starting point too,
Thanks Andru
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