The default link text is Expand / Collapse. This can be changed by configuring the extension.

Example

For these examples the extension is configured to use the link text: Custom Linktext.

Given the spec reads like this:

<div id="id" class="collapsible">This should be collapsible.</div>

When run the output is enhanced with the needed code for the collapse feature:

<div class="toggleContainer">
    <a href="javascript:Collapsible.collapseExpand('id');">Custom Linktext</a>
    <div id="id" class="collapsible" collapsed-height="1.5" collapsed-height-unit="em" style="height: 1.5em;">This should be collapsible.</div>
</div>

Set link text

Example