Forgejo is changing its license to a Copyleft license. This blog post will try to bring clarity about the impact to you, explain the motivation behind this change and answer some questions you might have.
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Developers who choose to publish their work under a copyleft license are excluded from participating in software that is published under a permissive license. That is at the opposite of the core values of the Forgejo project and in June 2023 it was decided to also accept copylefted contributions. A year later, in August 2024, the first pull request to take advantage of this opportunity was proposed and merged.
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Forgejo versions starting from v9.0 are now released under the GPL v3+ and earlier Forgejo versions, including v8.0 and v7.0 patch releases remain under the MIT license.
It seems there was a pre-existing agreement to use the GNU GPL with Forgejo, and it seems to me that the GNU AGPL is not compatible with the GNU GPL.
There is more discussion about that around https://codeberg.org/forgejo/discussions/issues/201
I’m assuming that there has been some resistance to using the GNU AGPL with Forgejo (it seems the discussions about licenses has been contentious), and the GNU GPL seems to have been discussed much more than the GNU AGPL. It was probably overwhelmingly likely that we would get Forgejo with the GNU GPL rather than the GNU AGPL. I would have preferred that the GNU AGPL was used instead, but I’m not going to worry about it much since I probably can’t change this situation for the better.
You’re right, seems like GPLv2 is incompatible with AGPL. GPLv3 includes extra clauses to allow it.
From the GNU Licensing page