Weblate is Web-based continuous localization platform, Copylefted libre software, used by over 2,500 libre software projects and companies in over 165 countries with version control support and much more!
It has great UX/UI compared to proprietary platforms such as Transifex and Crowdin and is very fast with multiple error checks.
Recently, 2 projects have migrated to Weblate this month (and many other projects too).
The dev of packagekit shared some info about weblate migration.
The developer shared their experience with migrating to Weblate here.
I encourage FOSS projects that still rely on proprietary platforms for translations, to migrate to Weblate as it will make much more intuitive and easier for translators to translate your project and for discovery.
And btw, Fedora is also using their own instance of Weblate managed by Weblate team.
