Hi, Laura-
Ah, based on your "noVNC" remark, is this happening when you are remotely logged in to another machine? That doesn't immediately suggest a solution to me, but that is interesting; what kind of system are you logging in from?
Presumably, you do get a normal AFNI selector/scrollbar menu if you hit the "Overlay" or "Underlay" button (which you would use to select an overlay or underlay to start with?
Normally, when you left click on the name of the subbrick, you get the large menu like you have (though, I guess it is so large that it is truncated for you?).
The way I got the scrollbar menu was by right-clicking on the 'Olay' button itself (not on the name of the subbrick immediately to its right).
Just to clarify, *that* isn't working (right-clicking on the word 'Olay' there)?
-pt