Hi,
I've just pushed my commits for show/hide column feature. If you have some time, please give it a try at [0] and let me know if you have any comment or suggestion.
When you are testing, please note that the feature still lack of some things: - column visibility list drop-down arrows are shown in "too many" places when display mode = vertical AND repeatCells = small number - the hide (small X) button is sometimes annoying, especially when we want to sort a small column (e.g., usually ID). I've tried to resize all columns using jQuery to properly display the "hide" button next to the column label. But, unfortunately, it is quite slow. Any other suggestion? Should we remove the "hide" button?
[0] http://demo.phpmyadmin.net/gsoc-aris
Regards, -- Aris Feryanto