[5] NodeRectViewer displays boxes (e.g. padding box, border box, and so on) displayed within your browser. Execute the bookmarklet below and see what occurs.
[7] <https://suika.suikawiki.org/www/css/noderect/nrv-snapshot-1.png>
[4] User interface part is implemented in <https://suika.suikawiki.org/www/css/noderect/NodeRectViewer.js>.
[3] Core part are implemented as separate JavaScript library: NR.js.
[6] All of major browser engines are supported.
[8] 似たようなのがあった: XRAY :: for web developers ( 版) <http://westciv.com/xray/>
[9] NodeRect.js ( 版) <https://suika.fam.cx/~wakaba/wiki/sw/n/NodeRect%2Ejs>