If you have Crayon Syntax and W3 Total Cache WordPress plug-ins installed and are experiencing issues on the front-end, read on…
Navigate in WordPress admin, to the following page: Performance -> Minify -> Advanced. Here, in this section of advanced options, you will find the control feature allowing you to exclude specific CSS files from the minification process.
You’ll want to put the full URL of crayon.min.css. You can use this properly rendered Crayon Syntax as a guide :^)