How do I select and move all the messages in a folder?

I can only see the option to select “all visible” which literally only selects what you can see on the screen, not even the messages that have scrolled off the bottom of the screen. This is just a few messages. How do I move ALL messages in a given folder from one folder to another? Or delete them all? Or mark all read, etc.?

A post was merged into an existing topic: Toggle to “select all” check boxes