I am using SyntaxHighlighter. I followed the installation steps and I'm receiving a few errors in the firebug console:
TypeError: SyntaxHighlighter is null
ReferenceError: XRegExp is not defined
I imported the necessary files.
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Why I am getting these errors?
It sounds like you need to put your XRegExp.js reference before the shCore.js reference. Order does matter when there's a dependency. One of the most common examples being that you have to load jQuery before you can use jQueryUI.