Show extra lessons in which a person is the new teacher in "My timetable"

added part::backend part::frontend prio::1 source::customer type::bug labels

changed title from Show substitutions/extra lessons/events in which a person is the new teacher in "My timetable" to Show extra lessons in which a person is the new teacher in "My timetable"

After some debugging, I found out that just extra lessons are affected. Bug is written and MR will be opened soon.

created merge request !91 (merged) to address this issue

mentioned in merge request !91 (merged)

closed with merge request !91 (merged)

mentioned in commit 85f455d7