Comment 2 for bug 1769581

according to the code, the options in the 'Choose an action' dropdown are these:

for a moderator/admin of the forum (also subscribed to the forum)
Sticky, Unsticky, Close, Open, Move to

for a moderator/admin (not subscribed to the forum)
Subscribe, Unsubscribe, Sticky, Unsticky, Close, Open, Move to

for a member (not subscribed to the forum)
Subscribe, Unsubscribe

for a member (subscribed to the forum)
no actions

It looks like if you are not subscribed to the forum, you can subscribe/unsubcribe to the individual topics. it's not related to being admin, moderator or normal user.
.