Suggestion: display CSS sizes in Compatibility Tool (move manifest) #2169
Description
@billerickson had a good suggestion, that it would be useful to display the CSS sizes in the Compatibility Tool.
It would help developers see how close they are to the limit.
This could include the total CSS size for all files, the size of each file or <style> element, and the source of each.
It might be similar to the comment printed above the <style amp-custom>. For example, in https://make.xwp.co/?amp:
<!--
The style[amp-custom] element is populated with:
0 B: style[amp-custom=]
198 B: link#twentyfifteen-jetpack-css[rel=stylesheet][id=twentyfifteen-jetpack-css][href=https://make.xwp.co/wp-content/plugins/jetpack/modules/theme-tools/compat/twentyfifteen.css?ver=6.5][type=text/css][media=all]
86 B: link#jetpack_related-posts-css[rel=stylesheet][id=jetpack_related-posts-css][href=https://make.xwp.co/wp-content/plugins/jetpack/modules/related-posts/related-posts.css?ver=20150408][type=text/css][media=all]
0 B: style#jetpack_related-posts-inline-css[id=jetpack_related-posts-inline-css][type=text/css]
403 B: link#dashicons-css[rel=stylesheet][id=dashicons-css][href=https://make.xwp.co/wp-includes/css/dashicons.min.css?ver=4.9.8][type=text/css][media=all]
90 B: link#jetpack_likes-css[rel=stylesheet][id=jetpack_likes-css][href=https://make.xwp.co/wp-content/plugins/jetpack/modules/likes/style.css?ver=6.5][type=text/css][media=all]
942 B: link#genericons-css[rel=stylesheet][id=genericons-css][href=https://make.xwp.co/wp-content/plugins/jetpack/_inc/genericons/genericons/genericons.css?ver=3.1][type=text/css][media=all]
26293 B: link#twentyfifteen-style-css[rel=stylesheet][id=twentyfifteen-style-css][href=https://make.xwp.co/wp-content/themes/twentyfifteen/style.css?ver=1.9][type=text/css][media=all]
109 B: style#twentyfifteen-style-inline-css[id=twentyfifteen-style-inline-css][type=text/css]
253 B: link#jetpack-widget-social-icons-styles-css[rel=stylesheet][id=jetpack-widget-social-icons-styles-css][href=https://make.xwp.co/wp-content/plugins/jetpack/modules/widgets/social-icons/social-icons.css?ver=20170506][type=text/css][media=all]
0 B: link#amp-default-css[rel=stylesheet][id=amp-default-css][href=https://make.xwp.co/wp-content/plugins/amp/assets/css/amp-default.css?ver=1.0-beta4-ec11c489-20180924T013410Z][type=text/css][media=all]
886 B: link#make-xwp-style-css[rel=stylesheet][id=make-xwp-style-css][href=https://make.xwp.co/wp-content/themes/make-xwp/style.css?ver=0.2][type=text/css][media=all]
29 B: style[type=text/css]
0 B: style#syntaxhighlighteranchor[type=text/css][id=syntaxhighlighteranchor]
0 B: style#wp-custom-css[type=text/css][id=wp-custom-css]
0 B: link#jetpack-responsive-videos-style-css[rel=stylesheet][id=jetpack-responsive-videos-style-css][href=https://make.xwp.co/wp-content/plugins/jetpack/modules/theme-tools/responsive-videos/responsive-videos.css?ver=4.9.8][type=text/css][media=all]
75 B: div.amp-wp-cb45893[class=amp-wp-cb45893]
Total included size: 29364 bytes
-->
<style amp-custom>Related: #1801 (showing sizing information in the admin bar).