Electrum: display redeem script of a P2SH utxo
I did not find a good answer, so I coded a small GUI to perform signatures using private keys, verify a signature using a public key (or an address) and verify a p2sh M-of-N multisig script against a list of N public keys and the parameter M.
This information is easy to find with a simple right click on an address in Electrum (View Details).
https://github.com/PiRK/signverify
I made it primarily for BCHA, but it works for BTC if you paste a legacy p2sh address instead of a CashAddr.