I've done a tone of work to add Subresource Integrity output for externally loaded files on my site and I've tested extensively to make sure my sites are as secure and up to date as possible. But though I am able to generate an A+ rating on Mozilla Observatory I can never pass the 'Subresource Integrity' check and I simply can't understand why.
https://observatory.mozilla.org/analyze/icondds.com
Should I be adding Subresource Integrity code to my locally hosted files too?
Thanks for any insights.
Vince