I made a discovery today that will save me a lot of time when it comes to joining groups.
If you have hundreds of lenses like I do, it can be difficult to find the right lens why trying to join a group. One option is to try to scroll down until you find the right lens.
Tonight I found that there is an easier method. Simply move your cursor over the the top of the drop down menu where you find your lens title and start typing in the title of the lens that you want to submit to the group.
If you do this, the correct lens will show up and it can be a real time saver. Hope this helps.