Funny story but this bug caused me like half a days worth of trying to find whats wrong. When setting up the nodebb I made an admin with ' in its username. Results were weird to say the least. I could login, but I couldn't actually do anything when I did it, most of the buttons were not working. Basically usernames are sacred for some reason.
@baris Guess that should have been the obvious, and yeah, we had some code that would auto generate a background for users. Disabling that did fix it. I really appreciate the help, feel kind of stupid now lol. Besides that being fixed now we still have an ongoing issue with plugins not working like emoji's, shoutbox, and so on. And words of advice on that?