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

https://github.com/Duncaen/void-packages firefox-esr-102
https://github.com/void-linux/void-packages/pull/39677

firefox-esr: update to 102.3.0.
- [x] x86_64-glibc
- [ ] i686-glibc
- [ ] aarch64-musl
- [ ] armv7l-musl

A patch file from https://github.com/void-linux/void-packages/pull/39677.patch is attached