[split] Alerts not showing up for tagged pms

I'm going to add to this that sometimes — not always — I don't receive 'You've Been Tagged' pm's even though I clearly have been — I've noticed this on both Wintersbane and Praimfaya's accounts.

Specifically, I did not get this tag on Praimfaya's account or this one on Wintersbane ...although looking at it I'm not real sure what happened to most of the character tags in the Wintersbane thread. Looks like they just colored as links and didn't actually tag?

To clarify, it's not an issue of my inboxes being full because I clean them out regularly so that's never an issue.

I went ahead and split this out bc I'm guessing it has more to do with the tag plug-in than anything else!

(I'm going to wrap a fix for this into the one I already have ready to go for username special characters)