Not sure this is a bug but this happened to me a few times lately. I am running Version 3.2.1 (4468; Integration v. 176). After invoking Hook on a web URL , it seems to have frozen showing the beachball when the mouse is hovered near the dialog screen. I tried to look for a way to force quit it but could not find that in any menu.
To give an example , the previous hook dialog still would not go away when I logged into this forum