Screenshot feature broken

[BobbinT]

I use a Controller and with this feature enabled you can press the Back+Start for Xbox style or Select+Start for Playstation style controllers.
Not sure about the Keyboard combo, but with the Controller you press Back or Select first then press Start to take the screenshot, as it will not take a proper screenshot unless the HUD is hidden, which is what Back/Select on the pad does.
This allows you to take multiple screenshots in succession which is what you wanted to do, they are saved in the directory that is specified in the ffxiconfig program.

keyboard equivalent is Scroll Lock, right beside Print Screen button.

also...

recently got answer from discord, not sure if this is actually applies, but it does work for some reason while it doesn't really make sense:
Scroll Lock, then press Print Screen and F11.

2 discord channel including reddit ones actually post similar ways.