Preview shortcuts to select editor tabs by index I am trying to switch rapidly back and forth between two related Preview tabs (different versions of a research paper). In other applications I would do this by selecting Command-[TabNumber]  e.g. Command-3 then Command-4 then back to Command-3.  

What is the equivalent in Preview?  I did look at the help https://support.apple.com/guide/preview/preview-keyboard-shortcuts-on-mac-cpprvw0003/mac
 and also just tried a number of combinations without luck.
In Preview you can do the following:


Open the two documents in their windows;
Go to menu Window and click on "Merge All Windows"; this will merge the windows into tabs inside Preview.
Now you are ready to switch between tabs with Ctrl+Tab to go to next tab, or with Ctrl+Shift+Tab for previous tab.