Also worth checking out tabs-rs[1] which seems very well reviewed & recent.
Personally, I am a huge fan of dtach[2][3], which isn't a multiplexer, just a detachable proxier of terminal sessions. This let's me run a persistent vim session that I can reconnect to, and vim has however many terminals I need open in it. Vim does my multiplexing, dtach just allows me to make vim persistent. Very glad to have re-discovered dtach, to enable this workflow.
Notably dtach is very lightweight. Unlike tmux, it is not a virtual terminal. Upon reconnect to my vim session, I issue a control-l to refresh the screen. Dtach hasn't retained the screen state, isn't translating between terminfos. The one thing that can go wrong here is connecting from different terminals- few programs have a way to update the TERM setting once the program has launched.
[1] https://github.com/austinjones/tab-rs