Change edit window width
Fragment of a discussion from Project:Support desk
After some checking found it myself. It is really easy, however needed some time :-)
hi -
What about you share with everybody how you did it ..? :d
My guess would be using CSS such as textarea#wpTextbox1 { width: 100em; } although I have not tried it myself.
(edit)
You can change it in My preferences.
Allen4names (talk)