Tor Browser 8.0.4 stops working correctly in Virtualbox on Windows

Starting with https://blog.torproject.org/comment/278874#comment-278874 we got some feedback that text on some websites is not working properly starting with 8.0.4 on Windows once Tor Browser is run inside Virtualbox.

8.5a3 is the first alpha release that shows this behavior (https://blog.torproject.org/comment/279184#comment-279184) although it's not obvious how this is related as none of the 8.5a3 changes made it into 8.0.4 it seems.

I did not try to reproduce the issue yet.