seems like the need here is for a graphical terminal. a terminal that displays graphics which are sent to it as graphics, and not as ascii-encoded binary.

the default terminal in plan9 could do this, though i don't know of anything which took advantage of it outside of plan9 itself. you could open a new window (which is a terminal with a prompt and a cursor and a shell and so on), and type the command to launch the window manager ("rio") and it would launch a new window manager inside your terminal window.

it's not even really fair to call plan9 windows "terminals" since they're plan9 windows and anything that can be displayed on plan9 can be displayed in one.

the neater stuff comes when you use one of those plan9 windows to remote into another machine and run a graphical tool inside it. you could run the window manager of the remote machine and display it locally, all through normal commands you used all the time and without any special software, and you could open more plan9 windows inside that window manager inside your local plan9 window inside your local window manager. all over the 9p protocol that plan9 used for everything. 9p is used all over the place today, but only for relatively niche things.

i think we've really ignored a lot of what plan9 did, to our detriment as an industry.