With RC3, Win 10, when I first dock the defs toolwindow at the right hand side of the mdi window, the horizontal scrollbar in the defs tw works normally. Close slick, then re-open, now the defs hz scrollbar doesn't work properly. It thinks the logical width of the tw is the physical width and prevents me from scrolling the tw to see all the content.
I noticed this because of the fairly large amount of space wasted at the left hand side of the defs toolwindow so I decided to see if I could get rid of the wasted space by scrolling the window sideways but it won't let me scroll it, except after I first dock it.