There is an updated pull request by ar-jan against master on the void-packages repository

https://github.com/ar-jan/void-packages electrum-409
https://github.com/void-linux/void-packages/pull/28305

[WIP] Update Electrum to 4.0.9
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#### General
- [ ] This is a new package and it conforms to the [quality requirements](https://github.com/void-linux/void-packages/blob/master/Manual.md#quality-requirements)

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- [ ] I use the packages affected by the proposed changes on a regular basis and confirm this PR works for me
- [x] I generally don't use the affected packages but briefly tested this PR

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This depends on #28272.

I've added the package [libbitcoin-secp256k1](https://github.com/void-linux/void-packages/tree/master/srcpkgs/libbitcoin-secp256k1) as dependency, but: it is based on this release: https://github.com/libbitcoin/secp256k1/releases/tag/v0.1.0.13 with the last commit included dating to December 2016. Electrum currently [uses](https://github.com/spesmilo/electrum/blob/master/contrib/make_libsecp256k1.sh) a commit from from June 2020 from https://github.com/bitcoin-core/secp256k1.

Remaining issues:

- The package builds and runs OK (tested opening and creating wallets), but I don't know if the oudated libsecp256k1 could be problematic with other functionality.
- Difference between libbitcoin/secp256k1 and its upstream bitcoin-core/secp256k1? Possible to provide the bitcoin-core/secp256k1 version instead in Void?

A patch file from https://github.com/void-linux/void-packages/pull/28305.patch is attached