Okay double checked, it's in your Options menu, under Keymapping, scroll down to the bottom, where it starts under the Other heading, and find Toggle Screenshot UI, set some button to that, and should take the screen while you have your personal ID open on one side of your toon... I usually just set the button to hide the UI, since I want reference shots without type...
Hope that helps...
if you don't want to map a key,
/screenshotui 1
turns ON UI in screenshots.
/screenshotui 0
turns it off.
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Quickest way to just take that one picture is to have a paint program open, take your screenshot, and immediately control-paste into the paint program.
The image will save in your screenshots folder the same way, but you can save the pasted version however you like, and it will have exactly what you see on the screen.
Otherwise, yeah - in Options / keybinds you can set your UI as a TOGGLE, it's not a click option, it's a TOGGLE, so be careful how many times you click it 
I usually set mine to 'shift-printscreen' so I can click that once, take screenies using printscreen, and then shift-prtscrn again to take normal ones without the UI.
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Repurposed
Thanks all.
I have a puestion you've probably been asked dozens of times, but how do you take a screenshot so your personal ID shows? I just keep getting shots of my character, without the ID info.
Thanks,
Miz