This is in 7A21, on 10.13.3, 17D34a
If you have two scripts in a window, tabbed, and you drag one out, the one you drag out will drop about 2-3" every time you click on the title bar. Doesn’t matter the script, and it’s always the tab that is dragged out that does this. Clicking the close/minimize controls works as expected. I tested it with three tabs, same behavior.