Make region an optional parameter in the search
Invidious still doesn't support all regions that youtube does, and currently the implementation is practically broken entirely, so the search may not work.
With my system in pt-br, plasmatube does not display any results for searches and return this error
There is already an issue open to monitor the progress of this work
https://github.com/iv-org/invidious/issues/2021
And others related that also relate to a better internationalization of invidious
https://github.com/iv-org/invidious/issues/476
https://github.com/iv-org/invidious/issues/1279
https://github.com/iv-org/invidious/issues/2036
In short, invidious is still not able to handle different regions very well, so plasmatube shouldn't pass this flag. But at least there is work in progress that will make this possible soon