electrum rpc batch request not working

[greenaddress]

I tried to send an electrum rpc batch request for blockchain.transaction.get with several txid and I don't think I ever got a response back.

Either is not implemented at all or there's a bug. Works on original electrs, electrumx and fulcrum.
Example request that failed:

[{"jsonrpc":"2.0","id":"2","method":"blockchain.transaction.get","params":["a0d1ec3d3b821c86f36dcea5767b92e952c7337e1ad2b591467d9c9e61e70b06"]},{"jsonrpc":"2.0","id":"2-1","method":"blockchain.transaction.get","params":["83b54434a7dd45db6e06c519381a57dda30e8173c15a8232fa3dd9216cbe4940"]}]

For example in bash

echo '[{"jsonrpc":"2.0","id":"2","method":"blockchain.transaction.get","params":["a0d1ec3d3b821c86f36dcea5767b92e952c7337e1ad2b591467d9c9e61e70b06"]},{"jsonrpc":"2.0","id":"2","method":"blockchain.transaction.get","params":["83b54434a7dd45db6e06c519381a57dda30e8173c15a8232fa3dd9216cbe4940"]}]' | nc bitcoin.aranguren.org 50001

you get

[{"id":"2","jsonrpc":"2.0","result":"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"},{"id":"2","jsonrpc":"2.0","result":"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"}]

with

echo '[{"jsonrpc":"2.0","id":"2","method":"blockchain.transaction.get","params":["a0d1ec3d3b821c86f36dcea5767b92e952c7337e1ad2b591467d9c9e61e70b06"]},{"jsonrpc":"2.0","id":"2","method":"blockchain.transaction.get","params":["83b54434a7dd45db6e06c519381a57dda30e8173c15a8232fa3dd9216cbe4940"]}]' | nc electrum.blockstream.info  50001

we get nothing (it just returns)

for other non batched requests it works as expected

echo '{"jsonrpc": "2.0", "method": "server.version", "id": 0}' | nc electrum.blockstream.info 50001

{"id":0,"jsonrpc":"2.0","result":["electrs-esplora 0.4.1","1.4"]}

[greenaddress]

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