I'm a BIG fan of OSI HM-270 construction silicone sealant...

Excellent for use on non porus materials (glazing glass)
Service temp. -60 deg. F - +400 deg. F
Waterproof & weatherproof
Virtually unaffected by weathering
+ or - 25% movement capability

For use on, but not limited to:
Skylights
Solar panels
Windows & Doors
(all that from the label)

I discovered this stuff back in the day, when I built all glass sunrooms.
I've used it on the VX for everything from re-gluing the headlight gaskets, to re-fastening the roof chanel filler pieces.

Call a few lumber yards/construction suppliers, you MAY be able to find it at a big box...(Lowes, Menards, Home Depot)
It also comes in a variety of lovely shades, but I've personally never had much use for anything other than black & clear.

Also, do a nice job of masking on either side of what you're sealing, strike the bead down with a moist finger & peel the tape for a top notch finished appearance...

Have lots of rags/paper towels @ the ready...