First of all, the copyright license of the MySQL logos is GPL; Firefox's logos are "all rights reserved". Before trademark enters the picture, Firefox's logos already cannot be redistributed because of their copyright.
As for MySQL's trademark policy, read the first section (1A). It's not too hard to parse. """The "Conditional Use" Logos may be used without specific written permission from MySQL AB under the following conditions: ... If used in an application released under the GPL license, the application must be able to connect directly to a MySQL server""" -- Some components are non-free https://launchpad.net/bugs/83118 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
