I'm afraid it's possible to use #Electrum on #testnet, but it seems to be necessary to recompile it from source to allow it.

I've also found out that nostr: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 , nostr: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 , and #Eclair can also work on tesnet.

I'm now in the process of stacking enough t-sats on chain to be able to open a LN channel...