Theres bug where if you expand the popup window vertically, the contents dont expand with it. When I debugged it with google chrome, pressing f12, i found out that this was the case because the height of the content is hard-coded with style A hack-around fix is to press f12, click "new style rule" then add this code: .compendiumpopup.ui-dialog-content.ui-widget-content { height: 100% !important; } how you would actually fix it in code is to add this code to the css. .compendiumpopup.ui-dialog-content.ui-widget-content { height: 100%; } then, when the window itself gets created through javascript, assign the height to the window thats being created. Instead of assigning the height to the content