Question

In Bootstrap, How to make a link (button) which toggles a region.

My intention is to Show/Hide debug information kept in a <div>

Answer 1

This is nothing to do with bootstrap; it’s basic JavaScript.

Add an ID to the link, and to the <div /> you want to toggle, and then use the jQuery toggle() method (as jQuery is included with bootstrap).

$('#your_link_id').on('click', function () {
    $('#your_div_id').toggle();
});

You can even use slideToggle() instead of toggle() if you wanted a cool sliding effect.