Use the Toolbar at the top of the window to view or hide panels.
Click the buttons in the Toolbar to view/hide the following:
Click the input button to add panoramas via a dialog. You can also drag panoramas onto the Viewer to add them to the project.
Quick Share – Click to export the current panorama. The exported panorama will apply the default view so it is centered and if viewing limits have been applied, the image will be cropped to those limits.
A context menu is also available, giving you another way to add the panels or to hide the toolbar. Right-click in the Toolbar or any panel header to bring up the menu.