Alignment issue of WYSIWYG editor in the object editor

See problem 1 of attached screenshot.

For example, go to xwiki/bin/edit/IconThemesCode/IconPickerMacro?editor=object, in the WikiMacroParameterClass and look for "Parameter description"

Objective

Make sure the editor has the same size as the other form elements. Fix it either by using CSS or by providing the textarea sizes. Test your changes with multiple editors available in XWiki.