STR: (see GIF attachment) - Open inspector - Collapse the sidebar panel - Move the mouse right before the border of the window - Click and drag ER: "the window resizes" or nothing happens if you actually misclicked inside rather than on the border AR: the collapsed sidebar appears The same issue can be reproduced with the Variables/Events panel of the Debugger, the details panel of the Network etc... (basically every module that supports a collapsible panel)

Related issue: when the sidebar is collapsed or hidden the rightmost item your mouse will target is the splitter. When the window is maximized, it is very easy for the user to click on this when trying to click on the scrollbar. This second issue also affects webconsole and scratchpad, which have hidden side-panels. => see bug 1255603