Page → Manager... (P M) opens the page manager window where you can interactively walk through the open schematic pages.
Page → Previous (<, PgUp, or P P) comes to the page in the list of opened pages previous to what is currently shown in the page view.
Page → Next (>, PgDown, or P N) comes to the page in the list of opened pages next to what is currently shown in the page view.
Page → Close (P C, or F E) closes the page currently shown in the page view. If the page has any non-saved changes, the confirmation dialog will be shown where you can select saving or dropping changes, or cancel the operation.
Page → Revert... (P R or F R)
reverts all changes in the current schematic page since the last
saving. Since the operation is dangerous, the confirmation dialog
will be opened in order to prevent unwanted loss of data. It may be
useful though in cases when the page file has been changed by some
external program such as, for example, lepton-refdes_renum.
Page → Next Tab goes to the next tab. It is equivalent to Page → Next if tabbed view is enabled in configuration.
Page → Previous Tab goes to the previous tab. It is equivalent to Page → Previous if tabbed view is enabled in configuration.