Icon background

@immermanalu It looks like you’re using Yoast to place the logo in your reader mode AMP URLs. If so you can apply the below to the “Additional CSS” box with the (SEO > AMP > Design)

.amp-wp-header .amp-wp-site-icon {
background-color: transparent;
border: 0px solid #fff; 
}

Bear in mind the logo mentioned above is separate to your sites Favicon.

Thank you @jamesosborne for your reply.

No problem whatsoever @immermanalu, happy to help. Be sure to leave the plugin a review with your feedback.