A recent version of XCode (11 or 12) decided to change some of their default keyboard shortcuts, it seems, including some of my most used ones - namely, show previous window tab and show next window tab.

It turns out that they are now Ctrl+Shift+Tab and Ctrl+Tab. But that didn’t even work when I tried them.

After months of bumping up against this small friction, I found (perhaps unsurprisingly) that you can go into the XCode Preferences and setup whatever keyboard shortcuts suit your fancy, so I took care of that today by switching them back to what they were previously, namely Command+{ and Command+}.