I noticed a small bug, or so I believe it to be, on the group page (see image below)
The steps to reproduce this occurrence is to click on the button twice then move your mouse outside of the button and click again. This will cause the drop-down menu to open when you click outside of the button and close when you do click on the button, the opposite of what I would expect.
The same exact thing happens when I tried it on mobile.
This happens 100% of the time.
Can confirm that this happens not only on the group you mentioned in the post, but all groups. Are you using Chrome as well? (May be the browser, Chrome has been occasionally acting up for me recently.)
This is because when you click, there is a blue box around the button, which is on some websites when using TAB to control the website, hence why this type of behavior is happening.