Reproduced on Galaxy Tab S7, Files app crashes when browsing files from any browser or app.
I had the same issue on my Teclast M40 Tablet: Unable to attach any file to a message in any application (e-mail, WhatsApp, Skype, Facebook, etc...).
"File" application crashed all the time. This is the default app to attach a file, and no way to change this.
Because "File" is a factory pre installed application, I was unable to reinstall it or deactivate it, or stop it. I tried to clear cache & user info, no success.
Finally, I solved it: in the "File" application dedicated to accomplish this task. There is an option is the "File" application to activate "Display notifications" (it was deactivated). Then, miracle ! It works !
Very strange ! Maybe I did deactivate it, causing the problem because at the beggening, it was working fine. Better to take care when deactivating something...
I hope this info can help some of you...
Please let me know if ti worked for you.