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    Debugging CSS and JavaScript - Disabling the wro4j Tool

    This information is not applicable to Primo VE environments. For more details on Primo VE configuration, see Primo VE.

    This page is specific to the classic UI. For customization information that is specific to the new Primo UI, see New UI Customization - Best Practices.

    Primo utilizes the wro4j tool, which is used for analysis and optimization of Web resources ( As a result of this integration, the system will no longer fetch all CSS files for every page. Instead, a virtual CSS file called primo_library_css.css is fetched by the browser and cached until it has changed. The same is done with JavaScript files that are part of the system. This can affect developers who use tools such as Firebug by preventing them from displaying the complete list of CSS and JavaScript files. It also means that if the hierarchy of the CSS files has changed, the change will not be seen until the code tables have been deployed.
    The following figure shows the use of wro4j in a Primo search. Note that primo_library_css.css is a virtual file and cannot be viewed.
    wro4j Integrated in Primo Search
    With the use of wro4j in Primo, no file locations have changed and you should not expect or need to make any changes to your CSS files.
    To deactivate wro4J and display the actual CSS and JavaScript files that are being used by Primo, you can use a Web tool (such as FireBug) in your browser and append the wroDevMode=true parameter to the Primo URL, or you can add a bookmark to your browser's toolbar that contains the following JavaScript line, which appends the wroDevMode=true parameter to the current page when the bookmark is selected:
    The following figure shows the expanded list of CSS files that are being used for a Primo search.
    Expanded List off CSS Files in Primo Search