Oh man, I cant help you there, sorry.
The latest version I tried with RSS was 1.6.1, for some KSRSS fun. But I guess full size would work too.
Traditionally RSS was always a full version behind. The original creators would only release a new RSS version when KSP updated to the next full version, to avoid having to deal with the hotfixes IIRC. If this logic still applies you'd have to look into 1.10.1, but I dont follow the development anymore. A good bet would be to ask the Kopernicus crowd. They have a very lively Discord server going, btw. Pick a version that you know will work nicely, and pay attention to the versions of the dependencies.
Like I said, if I am in the mood for a full size RSS I fire up 1.2.2, works fine for me.
Dafni's post in RSS/RO Problems was marked as the answer