I created flight mode according to the documentation, checked several times. The problem is that my mode does not appear in the mission planner, does the mission planner take the list of available mods from the controller or are these static values in the mission planner itself?
No, it does not, you need to recompile and re-install mission planner.
I managed to install my mode via mavProxy by ID, are there any GCS that display a list of available mods using the list returned by mavlink, and so far I have not been able to find where to change the list of mods in the mission planner, I changed ParametersMetaData and nothing has changed(