Tried a run today on my Samsung A7 lite tablet. All worked well, but as I was going to type in the activity description, the background text prevented me from being able to read what I was typing.
Exactly the same issue on Xiaomi Pad 5. Don’t know exactly since when, I think it started about 2-3 updates ago.
Interesting. I wonder if this is exclusively an Android device issue because you know, if it happened on an iPad, we’d never hear the end of it! 
Just got done with a run on my Android Google Pixel 8 and when I went to edit the workout description, it sort of popped out into a form that I was able to easily read and edit. It appears that this issue might be fixed? Didn’t remember seeing it come out in any recent release notes.