Mobile device support, issues with the forum’s functionality or display.

I wanted to say that the quick edit seems to be working now, but I think I jumped the gun. The "save changes" button is pressed. The message seems to be updated. But the changes are not applied.
More precisely, I did this: I went into advanced mode, added some text with a quote to the message, saved the changes -> the text in the message did not change.
I went into quick edit mode, opened the message -> I see the changed text inside the edit window.
I press "save" -> nothing happens again.
See the previous message, plus screenshots from this one.
Configuration: updated Firefox, Win10, 1920x1080