Hide (not collapse) Right Tool Pane completely.
The collapsed Right Tool Pane violates usability principles. To quickly scroll a page, users can no longer just drag the mouse cursor all the way Right, to click on the Right scroll bar. This would probably take only 1 sec. With the annoying Right Tool Pane collapsed, nesting right beside the Right scroll bar, users must now carefully drag the mouse cursor, take aim so-as-to not click on the Right collapsed pane, then can he/ she click on the right scroll bar. This is really slow and inefficient.