Don't return MWEB-only transactions when `rpcserialversion` <= 1

[DavidBurkett]

spesmilo/electrumx#179 (comment)

[ynohtna92]

Any chance we can get this as a priority for the next release?

[DavidBurkett]

Any chance we can get this as a priority for the next release?

@ynohtna92 Yes! Can you take a look at this PR and see if it resolves the issue for you? We're still returning tx id's for the mempool entries from getrawmempool, but we return an RPC error when trying to query for MWEB-only transactions using getmempoolentry. From what I can tell after a quick glance at the electrumx code, that should work for you.
#885