It started to happen once around 5.2 came out and no there haven't been any noticeable changes to the device before the issue happened

1) Already been disable and don't have any "graphics driver-level programs" either
2) Mods are not the issue, already tested it because I didn't have mods in the first place when this happened. I didn't have any system mods before this happen.
3) It was "off" on default
4) Literally everything is already been disable, not the issue

I did try a factory rest on my PC, updated the drivers, set everything to the highest performance, and then only downloaded FFXIV and still got the fps issue. Recently there was one time I was doing a dungeon and the game automatically un-fullscreen me which was a first.