MDL-29996, all the 1.x filters will stop working for Moodle 2.5. Right now there are some custom filters running @ moodle.org still not updated:
- Geshi code highlighting
- Moodle docs link filter
- Moodle links filter
- Skype icons filter
This issue is about to update all them to be ready to work for Moodle 2.5, with any improvement & unit test support when possible.