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

https://github.com/Zapeth/void-packages firefox-esr-update
https://github.com/void-linux/void-packages/pull/46658

firefox-esr: update to 115.4.0
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#### Testing the changes
- I tested the changes in this PR: **briefly**

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#### Local build testing
- I built this PR locally for my native architecture, x86_64-glibc

[ci skip]

A patch file from https://github.com/void-linux/void-packages/pull/46658.patch is attached