There's a merged pull request on the void-packages repository

firefox-esr: update to 91.3.0.
https://github.com/void-linux/void-packages/pull/34167

Description:
Testing the changes:

- I tested the changes in this PR: briefly

Local build testing:

- I built this PR locally for my native architecture, x86_64-glibc

Note:

I use the Patches from Thunderbird and sync the template with Firefox. 

[skip CI]