This came up with issues #2380 and #2388 and PR #2783. I had been waiting for some internal feedback on my proposal but since this is now active I am sending in my API proposal for attaching plugin data to NetVConnections (TSVConn).
https://solidwallofcode.github.io/api/TSVConnArgs.en.html#tsvconnargs Some background on this proposal https://solidwallofcode.github.io/vconn-args.en.html
