I'm using ReShade version 18.104.22.1685 with Direct3D9 on Final Fantasy XIV (current version 4.35) using DirectX9.0c. DirectX version 12 is installed and up to date.
Setting the graphics configuration fullscreen mode (ScreenMode 1 under display settings in FFXIV_BOOT.conf) causes a fatal DirectX error ("A fatal DirectX error has occurred.(1000003d)") on startup. Both windowed and borderless windowed modes will load the game as expected. Error doesn't occur without reshade installed, no other settings seem to affect startup. The game can be changed to fullscreen once loaded without any problems.
Easy end-user solution is to play windowed/borderless (or to change once game is loaded, then back before exiting or through the config file after exiting.) but I figured a bug report would be handy anyway and I couldn't find anywhere else to send one.
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