I thought I updated this but a topper from a 12th gen "fits". The glass doesn't seal to the tailgate but I added weather stripping. I'll add photos from my phone.Found this thread with pictures that show the 13th Gen (2015-2020) does not fit:
https://www.f150gen14.com/forum/threads/2015-2020-canopy-topper-does-not-fit.1102/
I thought I updated this but a topper from a 12th gen "fits". The glass doesn't seal to the tailgate but I added weather stripping. I'll add photos from my phone.