What did you do to cause this?
Deleted some spam accounts that had been created during a period of high traffic on an older version of Traq.
What page were you on?
Examples of pages and how they break when users are removed:
What PHP and MariaDB versions do you run?
Describe the defect:
There should be some sort of failover in the event of deleted accounts, especially since there does not appear to be a way to restore the account once it has been deleted.
Because of this, it means numerous pages (as well as any page which depends on that page) are either no longer accessible, or have all formatting and style stripped while providing only partial content.
Since recent changes have allowed for the removal of elements from the timeline, I would imagine the ideal solution would be maintain the event / reference to the specific account which used to exist; however, do not provide a link to the user view.
In lieu of this, due to the scope of such a change, a fast compromise would be to, on inability to find an account reference, fill the field with "Anonymous" until a more suitable solution can be found. As it stands now, large portions of our Traq install are now inaccessible.
This should be fixed, I ran a quick test locally and it worked. However you may want to test it before running it on a production database, or at least after backing it up.