"Never again be stuck not being able to see cats do stupid things in animated gifs when you don't have your web browser available" Lol they do know how to sell their software xD. Thanks for link.

Tek emulation is very cool, and I wish it were possible to use it more... but the protocol doesn't allow you to clear parts of the screen, so the only way to undraw stuff is to clear the entire screen and redraw from scratch. This makes it really limited for interactive use.

(This limitation is there because the original display terminals used storage scopes with persistent phosphor --- there was no framebuffer, you just steered the electron beam around on the screen and lit areas stayed lit.)

I know it's not a traditional terminal, but GateOne actually has this. It's pretty interesting to use, weird to see a full quality picture in the middle of a terminal.

You can build xterm with sixel support https://github.com/saitoha/libsixel