I have a 6900XT connected to 2 monitors and a capture card. After updating my driver I noticed in COD:Warzone/COD:MW2 that the framerate option allowed in fullscreen exclusive mode is only 60 fps (there's no 120,144, 240, nothing), but if you select fullscreen borderless the framerate selection is locked so I guess it matches the refresh rate of the screen selected outside the game and you can play but with performance issues. If I disconnect the capture card completly this problem doesn't happen at all and if I select the second monitor the frame rate shows the 60,120,144 options.
Used DDU several tines to reach these conclusions:
Driver 23.4.3 works perfect with cloning and lets me select 240hz on main monitor while using the capture card
Driver 23.8.1 and Driver 23.9.1 only allow 60 fps Fullscreen exclusive on Main monitor with capture card
Something is broken with cloning in the recent drivers and will continue to be in the future since nobody noticed it