Is there any possibility that Events Manager would override something with blog categories? I’m having a strange issue where sometimes (and it seems random) blog categories send me to a blank page. If I go into Events Manager and save the settings again, the categories magically work again. Furthermore if I disable your plugin the categories work again. Here’s the strange part: if I deactivate and reactivate your plugin the categories work again but at some point, unknown to me, the categories stop working.
This is not related to just Event categories but also Blog categories.