For Fujifilm, it is particularly complicated and confusing!
Here we have the FUJIX DS-1P presented at Photokina in 1988
Unfortunately, it was never marketed, and there are only a few copies of this camera.
See here for more information.
petapixel.com/2016/06/09/photo-history-worlds-first-fully-digital-camera-invented-fuji/
www.digitalkameramuseum.de/en/cameras/item/fujix-ds-1p-3
camera-wiki.org/wiki/Fujix_DS-1P
The follow-up to the 1989 FUJI X DS-X
Which does not seem to have been marketed, too!
See here for more information.
www.digitalkameramuseum.de/en/cameras/item/fujix-ds-x
The first that seems to have been sold by Fujifilm is the 1991 Fuji DS-100
And I found a copy on eBay in the year 2000
Fujix DS-100 (1991) by Marc Aubry, sur Flickr
I talk about it here: My Little History of Digital Compacts
dprevived.com/t/my-little-history-of-digital-compacts/381/