Multi-sig support

[tupui]

What problem does your feature solve?

Fully support all multisig operations. Stellar's doc is big on how awesome Stellar is with multisig. Yet trying to make a transaction with a multisig wallet does not work:

Status 400: op_bad_auth
One or more operations in this transaction failed.

What would you like to see?

At the very least, the wallet should detect that the account is a multisig and let users sign multiple times if needed.

What alternatives are there?

The ecosystem is thin. There is Lobstr Vault and AFAIK that's about it. I went to develop my own solution https://stellar-stratum.xyz (there is a link to the repo at the top right, feel free to have a look)