Forum move discussions: Should not let you move to forums you don't have write access to

About moving forum discussions.

Currently, if you have mod/forum:movediscussions in a forum, you can move posts to any other forum in the site that you can see (coursemodule_visible_for_user).

This causes problems because:

a) You can move a post into a forum where you would not ordinarily be able to post to, meaning that anyone who has move permission on any forum can sidestep 'read-only' restrictions.

b) You can move a post into a forum by accident (ie intending to move it, but accidentally pick the wrong forum) and then cannot undo that mistake because you aren't allowed to move posts out of the target forum.

My suggestion is that either:

1) you should only be able to move a discussion if you have mod/forum:movediscussions in the destination forum as well as the source forum (ie so you can move it back if needed). This is my preferred option that deals with both a and b above.

OR

2) you must at least be able to start a discussion in the destination forum. This only deals with a above.

I'd like to make this change in 1.9.x if possible, otherwise can do just 2.x. Any opinions?