[einpoklum]

First, I suggest you try to use terminfo to properly ensure your terminal supports the "main subset" you've mentioned.

Second, I suggest you get in contact with Thomas E. Dickey, the maintainer of libncurses and terminfo, to see how he tests that library - on something like 15 different platforms.

Finally, over time, consider relaxing your set of terminal requirements - either with workarounds or with limitation of functionality for less-capable terminals.

[ncmncm]

I guess that working with more primitive terminals would make easier to use to drive UIs on embedded targets. The "terminal" Ftxui sees becomes just some LCD-painting primitives.