This has returned to meta. Chrome on window desktop, but not in safe-mode.
I cannot edit any text by selecting a word or phrase and using the editor toolbar (either using the select edit feature or the regular pencil icon). I could not make a word preformatted text or bold or whatever. The cursor jumps to the beginning of the text in the editor window as soon as the mouse cursor leaves the editor window area. Seems related to the mouse and non-touchscreen interface in a TC or plugin 
It is not happening in desktop view on my iPad Safari iOS.