[PythonicAlpha]

What about Trix?

Froala was already mentioned, I also heard about an editor namend Trix, that also claims not to use ContentEditable.

http://trix-editor.org/

Any experiences with that?

[ivanhoe]

Actually they say: "Trix sidesteps these inconsistencies by treating contenteditable as an I/O device". They use it to capture the input, which they then process and pump it back into the contenteditable. So technically speaking they do use it, just in a weird way.