You said that you can’t use HTML comments because the CMS filters them out. So I assume that you really want to hide this content and you don’t need to display it ever.
In that case, you shouldn’t use CSS (only), as you’d only play on the presentation level, not affecting the content level. Your content should also be hidden for user-agents ignoring the CSS (people using text browsers, feed readers, screen readers; bots; etc.).
In HTML5 there is the global hidden
attribute:
When specified on an element, it indicates that the element is not yet, or is no longer, directly relevant to the page's current state, or that it is being used to declare content to be reused by other parts of the page as opposed to being directly accessed by the user. User agents should not render elements that have the hidden
attribute specified.
Example (using the small
element here, because it’s an "attribution"):
<small hidden>Thanks to John Doe for this idea.</small>
As a fallback (for user-agents that don’t know the hidden
attribute), you can specify in your CSS:
[hidden] {display:none;}
An general element for plain text could be the script
element used as "data block":
<script type="text/plain" hidden>
Thanks to John Doe for this idea.
</script>
Alternatively, you could also use data-*
attributes on existing elements (resp. on new div
elements if you want to group some elements for the attribution):
<p data-attribution="Thanks to John Doe for this idea!">This is some visible example content …</p>
tag instead...
– TDsouza Apr 18 '13 at 13:02