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

Update Electrum to 4.0.9
<!-- Mark items with [x] where applicable -->

#### 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)

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

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#### Does it build and run successfully? 
(Please choose at least one native build and, if supported, at least one cross build. More are better.)
- [x] I built this PR locally for my native architecture, (ARCH-LIBC)
- [ ] I built this PR locally for these architectures (if supported. mark crossbuilds):
  - [ ] aarch64-musl
  - [ ] armv7l
  - [ ] armv6l-musl


~This depends on #28272.~

~Using package [libbitcoin-secp256k1](https://github.com/void-linux/void-packages/tree/master/srcpkgs/libbitcoin-secp256k1) as dependency might be possible, 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.~
--> The old version of `libbitcoin-secp256k1` in Void's repos is is sufficient for now, as per [this Electrum issue](https://github.com/spesmilo/electrum/issues/7014):

> if the tests pass, it is considered good enough. [to use the old libbitcoin-secp256k1]

So this is ready now. Also tested locally.

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