[1] Allow mathematical expressions in <img sizes> (musgravejw著, ) <https://github.com/whatwg/html/commit/5d091c267eff91529b032092c5214a3ffaf1928a>
[2] Allow min() and max() in <img sizes=""> · Issue #3003 · whatwg/html () <https://github.com/whatwg/html/issues/3003>
[3] Allow min() and max() for the image sizes attribute by GloverDonovan · Pull Request #3476 · whatwg/html () <https://github.com/whatwg/html/pull/3476>
[4] [3003] Allow mathematical expressions in image sizes by musgravejw · Pull Request #3084 · whatwg/html () <https://github.com/whatwg/html/pull/3084>