This is great remark: I haven't realized there is no such event handler like
onbeforeundo or anything similar what would be prerequisite for reliable way to revert to prior text value.
So again, is it really worth to be broken (but, eh, "fast") the same way like every other current browser?
Should we (web developers) really throw away textarea elements and switch to something like Codemirror the moment we decide to add something like "make bold" / "add signature" button?
It would be nice competitive advantage to have reliable text fields again. I'd really like to show off how I could return back to any state my field had, regardless how was its content formed.