Just freeze after update

Hi, I got just freeze after update to the latest. more than 2 minutes, then I unplug the power, then plug it again, still same. How to fix it?

Empty your browser cache. I also have the experience that it does not work with iPhone 4.

I access port 5000, then reboot app. It solved. Thank you @tobias-dahms for the reply. If next time got same issue, I will try your suggestion.