I do not really know what I’ve done to get that window, but look by yourself:
That window have two Tabs…
This is a Xojo 2015r1 project and this window is not meant to look like that; its size stops at some pixels below the flags (20 pxels); the window in the other Tab have this size.
The only thing I’ve done differently while running in the IDE, was to add Command-Option-N as a shortcut for the Linux window, then run and press the keys.
I didn’t know it was possible …
High Sierra (a buggy one, apparenly).