As for the topic itself:
The forum software has 2 settings:
- allow users to delete their own posts (this is allowed)
- allow users to delete their own threads (this is not allowed)
Apparently the latter means, that you can also not delete your post, if that post is the first in a thread. (even if there are no replies). So that can not be changed. its what the forum software allows.
"Allow to delete own thread" will stay disabled. Because it allows any one to delete replies made by others in that thread. However: Deleting other peoples post is something reserved to moderators.
In the past the delete-thread was allowed. This was never intentional. So when (after it was abused) we realized the situation it was disabled.
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If anyone needs their topic deleted (and it has no replies by others yet), then simply:
- lock the topic (so no replies will be added by any one)
- report your own topic.