CSS seems to be completely messed up on Windows Phone 10 / Edge

Hi everyone

So I just installed the very latest version of Nextcloud, 15.0.0, on a hosted server (I know it’s running Linux, but I have no information what version), and everything is working very well… except… when I use Edge browser on my Windows 10 phone to view the site, it looks like the screenshot linked below. Something seems to be seriously wrong with the CSS for mobile browsers. Any ideas how to fix this?

Screenshot: https://i.imgur.com/r14Hq2M.png

Edit: I just checked and it displays perfectly on Windows Phone 8.1 with IE browser.

@jan do you need more information and help from the user to debug this problem?

Just installed Nextcloud 15.0.2 and mobile CSS is still messed up.

Just create a bug report on github.com/nextcloud/server/issues