[smoldesu]

There's also Planner[0] if you're on Linux, a FOSS Things clone that actually gets a lot of stuff right for being free software. Just be sure to compile it yourself if you intend on using it, the current distribution method has been... rather disastrous[1].

[0] https://github.com/alainm23/planner

[1] https://twitter.com/planner_todo/status/1492084099875586049

[makeworld]

Flatpak will work, but you have to install from an older commit, not the one that installs the beta v3.

https://github.com/alainm23/planner/issues/852

[smoldesu]

I'd really only opt for Flatpaks if it was more stable than system packages. As we've seen with Planner, that's not necessarily the case...