The jellybean color scheme tries to provide fallbacks for when fewer colors are available from the terminal. When less than 256 colors are available (to be more exact, less than 88), it will try to use "White over Grey" for the
Pmenu highlight group. And when there are only 8 colors available (NR-8), then both "White" and "Grey" map to the same color 7. So that's probably what was happening.
I believe the best solution is to set up your terminal to use 256 colors. Most modern terminals support 256 colors these days (and some even more), so there's little reason not to use that.
In Vim itself, you can set that up using this command in your vimrc:
Or you can fix that in your terminal itself or the shell, by having it set a
$TERM variable to a terminfo/termcap entry that has 256 color support. For instance, if you currently have
TERM=xterm, then switching to
TERM=xterm-256color would fix that in Vim and in other applications that want to use terminal colors and want to query how many colors the terminal supports.
(You can always use
:set t_Co? to check how many colors Vim thinks the terminal supports.)
(If you decide to fix that in your terminal so other programs you run will also get fixed, I suggest you post a question in a more appropriate forum, depending on which OS you're on. Make sure you mention which terminal program you're using, whether you're using
screen, and what the value of the
$TERM variable currently is.)