KeePassRPC 1.9 includes a fix for an issue that meant the database default configuration did not always apply to the match accuracy of an entry, which may be at least a part of what is causing confusion here. I’ve also created a new documentation page that discusses what goes wrong when the PSL can’t be used, including an edge case where per-site URL overrides can’t take effect - again, that might explain some issues being described here but there are definitely some pieces of the puzzle still missing.
I’ve also combined some existing information about minimum URL matching, updated it and posted it in a new documentation topic.
I’m afraid that after days of investigation, I still can’t explain all of the behaviour described in this and similar topics but I think the time has come to draw a line under this topic because it already contains a variety of related but different issues so I’m closing it now.
After you upgrade to Kee 3.1 and KeePassRPC 1.9 please check if you still see match behaviour that can’t be explained by the new documentation and post a new topic with detailed information about what system, database and entry configuration you have, what is going wrong and what you expect to happen.