After installing Minify Jss / CSS / HTML extension, you can verify it's working by doing one of these solutions.

Solution #1: Check your minification folder

  1. Go to your store home page URL and View the Page Source.
  2. Search the page for “.js” until you find a file in the /extendware/ewminify/ directory
  3. Copy the URL and view it in your browser. You will be able to see if it is minified or not. 

Solution #2: Check minification with google PageSpeed insights

  1. Go to https://developers.google.com/speed/pagespeed/insights/ and input the URL of their site
  2. Look to see if it says "Minify JS / CSS" rules. If it does click “See how to fix”
    1. Note : Any file listed on an external domain you can ignore
  3. Any file listed <= 2% you can ignore as this is just testing error or it is because though it could be minified any more. 
    1. Note : Some restricted items in a Magento store can not be minified or else it will break the entire store. So some files may not be minified for your protection.
  4. If you see files NOT on an external domain and also not in /extendware/ewminify/, then you can add these files to the "Non-Standard files list". To do this, go to Extendware -> Manage Extensions -> Minify JS / CSS -> Configure -> Files, add their relative paths. Save your changes and then click the "Minify Non-Standard Files" button.
  5. If you are seeing lots of files that are not minified, then you may need to change the minifiers used in Extendware -> Manage Extensions -> Minify JS / CSS -> Configure -> Files. Try by clicking the “Auto Configure” button.