JS error:"jQuery is not defined" after enabling LiteMage

Problem: After enabling LiteMage, Magento shows the JS error “jQuery is not defined”. This error can also be seen from the Chrome/Firefox development console.

Cause: LiteMage uses ESI to hole punch certain blocks which are then used by LiteSpeed Web Server when assembling the main HTML page. Each ESI block is a different HTTP response and each of these responses will pass through the minify filter. When a hole punched block (ESI block) also contain javascript, the javascript minifier filter will process the partial HTML again, causing incompatible javascript references for the whole page.

Solution: Locate the module throwing this error, the pagespeed module in this example, and either disable it or modify it's configuration settings. For this case, pagespeed's Javascript “Enabled” setting had to be changed from “Yes” to “No”.