When I upgraded my server for My website from ubuntu 14.04, I moved my drupal 8 installation. I've never done this before, but it didn't seem like it should be hard, so I just went for it. I regularly do mysql dumps of my database from a cron job that saves the files. Therefore, I simply ran mysql, and then source database.sql (Much longer name though). Then, I placed drupal in the appropriate location, and since 8.1.7 had come out, it was the new version. I copied everything in sites/ over again, so that settings.php existed. Then, I got a error in php when trying to log into my admin account and some random other things, so I researched it, and installed php-xml (Something like that it's called) which fixed the error. After this, everything seemed fine, until I tried to collapse the management toolbar (I use a screen reader, so maybe it's visually collapsing and not announcing this, but I doubt it). Also, when I went to add a blog post, the rich text editor had no formatting buttons, and none of the collapsible (And normally collapsed by default sections) were collapsed. They simply acted as if they were not an accordion style forum. Plus, the rich text editor usually has a role of application, which makes a screen reader treat the editor as an embeded application. The shortcut to get to the menus, (Alt+f10) didn't do anything, and I'm pretty sure the rich text part from ckEditor aren't even loading. These errors are showing up in my browser console.
Error
The stylesheet https://derekriemer.com/?oang6p was not loaded because its MIME type, "text/html", is not "text/css".
admin
Error
SyntaxError: expected expression, got '<'
/
:1:0

I'm quite confused about this error, because nginx is set up properly to return the correct mime type for css and javascript files (I have an include mime.types statement and checking the headers with curl validates that this is properly working). But I think this error must be stemming from the issue here, because various things are simply broken. Has anyone seen this error becore?