Edit: As mentioned in the comments below, typing just ResourceFunction["Mo"] results in a list of ResourceFunctions that have a name that starts with Mo. This is good enough for me although it would be convenient if typing just Mo would show both official functions and resource functions (in another color).
I wonder if it is possible to use ToolTip, MouseOver and the likes in a way that, while writing, Mathematica proposes suggestions that incorporates ResourceFunctions rather than the current situation where it only shows official functions. Perhaps the resource functions can be colored in orange as a sort of warning that there is no guarantee that the function will work.
There is already a resource function that searches for other resource functions but it requires the Cloud and I would rather that Mathematica gives suggestions while typing.
Hence, I suppose this question has two parts:
How to get the list of all resource functions ? (Is it allowed to use web scraping to get that ? Maybe it can be extracted from the documentation center instead ?)
How to make a GUI interface that suggests elements in that list (ideally like Mathematica's autocomplete)?