I have a client running this addon and have had some odd issues that made us look into some of the code.
Could the following issues be resolved:
- Accessing PHP superglobals (like $_GET without filtering)
- No prepared statements in XenBulletins\KeyWordAlert\Repository\Queue::getQueus
- Missing indexes on table columns that used in JOIN clauses (high performance impact)
That was found doing a quick look, there may be some more to do once you get into the code deeper.