Problems with Dropbox Sharing in Safari

Sharing a folder on my Dropbox I usually have to use Firefox. If you go to http://www.dropbox.com and then 'Sharing' and then to a particular folder's 'Options' you get a list of people that you invited to your Dropbox in a separate window ('Shared folder options for ...')

Now you are supposed to be able to change the settings for each invitee/sharer by using a menue that you can get by klicking on the gear symbol. But Safari only displays a tiny arrow underneath the gear symbol and won't let me access the menue.

For comparison reasons here a screenshot from the same window first in Safari:

Notice the little arrow underneath the gear symbol. Now in Firefox:

Is it something I can change in Safari or is it a Safari bug? There is no possibility for me to report bugs, is there?

Thank you very much for your replies!

Konrad Stuhlmacher