Happened to me. Besides being an unbelievably irresponsible bug, the core functionality is terrible. I had an important document in my iCloud Drive and needed to send it urgently via email. This isn't possible on an iDevice. There is no file browser, you just have to open the file in the appropriate host app. And if that file type isn't one that can be opened by an iApp you are iFucked.
It does, but doesn't work in mobile browsers. I ws able to navigate to the webapp despite the site being not responsive, but I could only get it working as a desktop site in Chrome(anybody know how in safari?) and couldn't download or mail the file from there without getting a bug.
I don't know why I haven't heard it called iFucked before but that is brilliant. Please create an entry in Urban Dictionary for that.
The same with G Drive btw, it keeps wanting to send an f'ing G Drive link. It is such a denial of reality, this pretence that email attachments don't exist.