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

https://github.com/ericonr/void-packages firefox
https://github.com/void-linux/void-packages/pull/29712

Firefox 87.0
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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)

#### Have the results of the proposed changes been tested?
- [ ] 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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[ci-skip]

Have to figure out the musl build:

- fixed in new patch https://github.com/rust-lang/libc/issues/2121
- partly fixed but idk how to continue https://github.com/msirringhaus/minidump_writer_linux/issues/4

A patch file from https://github.com/void-linux/void-packages/pull/29712.patch is attached