I've got several devices with S2 that I have recently added to my mesh. There is a popup dialog box during inclusion that asked whether you want to "skip" security via a red box/button.
It seems that most of the time, clicking the skip button doesn't appear to do anything and the UI just freezes. In some browsers, there is text from below that is "bleeding through" across the top of the buttons. I would back out of this and it looks like the device was included properly without security, but it's concerning that it doesn't advance on its own and just stays on this screen.
I've tried this on Firefox, Chrome, Edge, and Vivaidi, all with different results. Looks like Firefox is the most stable. I don't know if this was reported before but there is definitely some issues here.