How can I keep the content I was reading from man after I quit?

Solution 1:

I believe this is not so much about man itself but rather about your pager of choice (PAGER environment variable) combined with the terminal in use.

I'm guessing your pager is probably less (typical default pager nowadays and fits with the description).

less has an option -X that may get you a behavior along the lines of what you're looking for.

   -X or --no-init
          Disables sending the termcap initialization and deinitialization
          strings  to  the  terminal.   This is sometimes desirable if the
          deinitialization string does something unnecessary, like  clear‐
          ing the screen.

Eg PAGER="less -X" man man could be used for testing it out, and if you find this behavior preferable you might consider setting PAGER to this value permanently.

Solution 2:

If you are running less as your pager (which is very common), you don't need to deal with modifying your pager, just do I/O redirection:

man <whatever you want to man> | cat -

This will print a copy to the terminal so you can scroll up when you need it.