I am using a style for the forum for version 1.6 and when creating a theme is deformed, take a look;
How fix that?
Thanks.
You have to increase the width of the textbox.
Have you already tried
this? Should fix the bug
Also try reducing the number of rows of the textarea in the newthread and newreply template.
using mybb 1.6 ? or upgraded ? then it must be fixed by default