Last column is auto spring one - that's the reason. Just resize whole form.
It's an option, but not one I prefer, since it's harder to see what you typed in in any field.
Also, if you make the mistake to make the Delete field really big, out of the window, you can't size it back anymore unless you know the Key combination Ctrl + +, which will size the columns to the minimum width required for the current value.
And I guess you want the interface to be as intuitive as possible, and this is completely unexpected behavior when I see a horizontal scrollbar.
If you size up the delete column out of the window.
If the category is selected click the white area, if not, click the category, the post will dissapear and a.b will give an access violation error. It wont crash the program tough, just keep giving that error when you click the white area.
If you click cancel after that, and then go back to categories, your post will be there again but sized really small.
And if you play a little longer with it, so size it up and make it dissapear, use ctrl + +, click cancel and go to categories again, hover over any post, it will give the following error: Bitmap image is not valid.
Yeah I guess I'm the only idiot trying that, but thats how people know me, breaking the most unexpected things.