I'm sure this is related to the beta.
Occasionally when I go into a plugins settings page since upgrading to RC3 (rc4 when I get a chance), it hangs on this page and crashes the entire webgui. Just sits there spinning, and at this point all I can do to get out of it is reboot the whole server.
Not sure if this is an issue with your plugins or specifically with the beta itself. Should I post somewhere that a dev knows this is going on? Haven't tried it with RC4 yet, will do that tomorrow. Wanted to post here just to mention it and see if anyone else is experiencing it.
Oh snap, I 'fixed' it. I went into htop and killed what I'm going to call a 'sub script' for emhttp. Looks like there was two that indicated it was checking on the sonarr version, I sent a kill command to each of those and it freed everything up and the webgui is working again. - I'll leave this here in case this is worth mentioning.