SmarterMail Popup window shrinks and cannot be resized in Firefox

Steps to block scripts from resizing windows:
1. In a Firefox new tab, type or paste about:config in the address bar and press Enter. Click the button promising to be careful. 
2. In the search box above the list, type or paste dom and pause while the list is filtered.
3. Double-click the dom.disable_window_move_resize preference to switch it from false to true.
4. Close all the tabs and restart the Firefox browser.