I can't resize the messenger window. I can't resize the contacts panel to show the names. The double arrow shows when I hold the cursor over the edge, but it won't drag.

The Messenger in the Sidebar allows me to have Messenger handy without running the Messenger app, but why can't I widen the left column (contacts)? Hard to identify people from their photos. I can't widen the message section either. It can't be my system, because I can widen windows just fine.