App License: Open Source (MPL/GPL/LGPL under Mozilla EULA)
While it was true originally, for the last 1.5 decades (since Firefox 13 in 2012) it has been strictly MPLv2.0.
There's a whole explanation about it in Wikipedia, with this source summarizing it:
The licencing on Firefox 13 has also changed. Now, rather than the old MPL 1.1 and disjunctive tri-licence, Firefox source and binaries are released under the Mozilla Public Licence 2.0.
The license's upgrade process was documented in Mozilla's wiki (starting with "We have a script which replaces existing tri-licence blocks with the MPL 2 boilerplate').
Please remember to likewise fix:
- Firefox ESR (Extended Support Release)
- Firefox Developer Edition
- Firefox Beta
- Firefox Nightly
- Legacy versions (they may be legacy but every single version there is still much newer than v13)
Thanks for the heads up
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