How to cache the CSS Fonts with Sharepoint

If you use your own CSS file with your own CSS fonts, then we’ll notice that Sharepoint doesn’t send cache headers if you use the below CSS code:

@font-face {
  font-family: 'Roboto';
  src: url('/_catalogs/masterpage/css/fonts/Roboto/Regular/Roboto-Regular.woff2') format('woff2'),
       url('/_catalogs/masterpage/css/fonts/Roboto/Regular/Roboto-Regular.woff') format('woff'),
       url('/_catalogs/masterpage/css/fonts/Roboto/Regular/Roboto-Regular.ttf') format('truetype');
  font-weight: 400;
  font-style: normal;
}

To have this resource sent back from the Sharepoint server with cache headers, you just need to add ?ctag=0 at the end:

@font-face {
  font-family: 'Roboto';
  src: url('/_catalogs/masterpage/css/fonts/Roboto/Regular/Roboto-Regular.woff2?ctag=0') format('woff2'),
       url('/_catalogs/masterpage/css/fonts/Roboto/Regular/Roboto-Regular.woff?ctag=0') format('woff'),
       url('/_catalogs/masterpage/css/fonts/Roboto/Regular/Roboto-Regular.ttf?ctag=0') format('truetype');
  font-weight: 400;
  font-style: normal;
}