You can fork such dual licensed project, add your own contributions and then Signal cannot use your code in anything they license to third-parties under non-AGPL. The fork becomes AGPL-only.
Example of where this has happened: MySQL was forked to MariaDB, so developments to MariaDB cannot be used by Oracle in their proprietary licensing of MySQL.
You're giving the company (in this case Signal) an open-ended license for your contributions whilst they don't return the favour. And so whilst they can offer a proprietary version e.g. Signal Pro with a friendlier license e.g. BSD you can't.
And what kind of underpins all of this is that many companies especially in the enterprise will not touch anything that is GPL or AGPL.
But for me AGPL is not in the spirit of FOSS. It's like you're an unpaid employee of some company who is happy to take your work as long as you don't compete with them.
I understand why AGPL was invented i.e. to prevent AWS ripping your project off but I don't think it's a particularly fair license for individual contributors.
[1] https://www.fsf.org/blogs/licensing/FSF-copyright-handling [2] https://lwn.net/Articles/857791/
Affero predates AWS by a lot. It was invented because FSF wants users to be able to see software they are using, but they cannot if it’s a remote server.
It has been used recently as magic anti-AWS wand, but it wasn’t built for that
edit: I am wrong in my dating! Affero is 2007, AWS was launched 2006. But yeah it was never meant as anti-AWS magic wand.
Aws , TiVo , whatever . Lots of orgs exploited the contractual logic gap in gpl v2. Aws is the latest in a long list of freeloaders .
I license all my / my startups code under AGPL v3. I don’t offer anyone proprietary license and I don’t ask anyone for CLA.
Defense against freeloaders and also tyrant. My operating agreement for my LLC has language about this stuff. It’s that core to our DNA.
With the CLA it's the same. But at least Signal give back by still providing libsignal as free software.
It depends on your motivations for contributing. If you don't like the CLA or any other things, you can still fork. Even if it may not be compatible with your own motivations, it is still in the spirit of free software.