Destructive SystemNotifications?

[Webrocker]

Hi,

here's what happened to one installation yesterday, and since I have no clue what triggered this, I hope some of you may have an idea and are willing to share.

While working with a superuser in the backend and modifying a page-template, adding/duplicating fields, suddenly the backend's theme changed and the backend behaved strangely. After logout, the page wasn't viewable - both front- and backend stated that the user had no rights to process the ProcessPageView module.

It took two people and four hours of debugging to get to the root of this: the system user template's fieldset had been modified and the only field left in there was 'notifications' -- all other fields were gone, so no user had any roles anymore. Immediately before the problems started a notification was saved to the database, stating 'welcome this is your first notification' (sorry for not being exact here, I'm writing this from memory without access to the actual messages), which is strange since the system notifiactions were active for weeks now and working fine.

my question is, how can a system notification / the systemnotification module/ alter the user template, or precisely, the user template's fieldset?

This was very hard to debug since at the first, second and third glance everything regarding roles, permissions and users seemed to be correct while looking at the database. the database itself was healthy, no repearable issues, no rogue data or strange overheads. Only the fieldset for the ser template was suddenly missing the usual fields which had been replaced (?) with the notification field.

Has anyone else had such an issue? I'll add the processwire version and versions of the modules used as soon as i'm at my working machine, and maybe @inspeCTor has some additional infos since he was the one working with the install when this happened.

it may be just a coincidence but since the timestamp of that strange message matches that of the start of the problem and the 'notification' field was the one left in the fieldset, I suspect the system notification module. but that's only guesswork and I'm happy for any idea/explanation for was going on here

EDIT: There was no attempt to update or modify the installation when this happened, just 'normal' development work with fields and templates while using a superuser

cheers,

Tom