This is something I found out recently, and may be of interest to other developers.
Consider this HTML code:
Now you would expect <div class="slab"> to be selected, and you'd be right for Chrome, IE and other browsers, but Firefox throws a wrench in by apparently selecting the first element with a class with the word "slab" in it (in this case <div class="slab-wrapper">)
The workaround will be to use:
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