[mister.freeze]

Well, the Krazy Glue didn't last long, a few days. I tried some double-sided tape I had laying around: it was good waterproof stuff. The adhesive worked but the foamy black substrate did not. I got some JB Weld Mirror Weld, trying that. Also picked up a different button; it's plastic but has a much bigger contact area for the glass. will try that next.