Silner on Nostr: I saw a list somewhere that listed some of the reasons. There are some that are as ...

I saw a list somewhere that listed some of the reasons. There are some that are as simple as a character limit and some that are just opaque but kept rejecting my posts anyway.

You can add your own relays in #coracle
https://coracle.social

And you can find a list here
https://nostr.watch/relays/find

There is one with better descriptions I've since lost, but its mostly trial and error anyway. Coracle will show you the rejections in a pop up after you post.