> * Changed the licence to GPL. (Raph agreed on that)
So it's probably just a typo in the article. Intended point is that the license was changed from Gzilla's private copyright notice[1] to the GPL of the time, which would probably be v2.
Nonetheless Dillo's code is also licensed under GPLv3 now.
This does not sound right. GPLv3 is much newer than that.