Hugo: Hugo CSS minify breaks AMP validation

[braderhart]

Description

Hugo is stripping the space after a parenthesis when doing minification. This happens when doing both resource minification, or when using the --minify option.

Un-minified:

body {
    -webkit-animation: -amp-start 8s steps(1,end) 0s 1 normal both;
    -moz-animation: -amp-start 8s steps(1,end) 0s 1 normal both;
    -ms-animation: -amp-start 8s steps(1,end) 0s 1 normal both;
    animation: -amp-start 8s steps(1,end) 0s 1 normal both
}

Minified:

body{-webkit-animation:-amp-start 8s steps(1,end)0s 1 normal both;-moz-animation:-amp-start 8s steps(1,end)0s 1 normal both;-ms-animation:-amp-start 8s steps(1,end)0s 1 normal both;animation:-amp-start 8s steps(1,end)0s 1 normal both}

The issue is here steps(1,end)0s.

Oddly, when testing with the minify module Hugo is using here it works correctly:

body{-webkit-animation:-amp-start 8s steps(1,end) 0s 1 normal both;-moz-animation:-amp-start 8s steps(1,end) 0s 1 normal both;-ms-animation:-amp-start 8s steps(1,end) 0s 1 normal both;animation:-amp-start 8s steps(1,end) 0s 1 normal both}

What version of Hugo are you using?

Hugo Static Site Generator v0.62.0/extended linux/amd64 BuildDate: unknown

Does the issue happen in the latest release?

Yes

[braderhart]

Duplicate of #6563

[apoorvmote]

Same issue with newly added built in minify options. Hugo version 0.68.3

The mandatory text inside tag 'head > style[amp-boilerplate]' is missing or incorrect.

[pperzyna]

I created an issue on tdewolff #300, because it is an intendant behavior of that lib.

[tdewolff]

This is fixed in v2.6.2 of minify. Hugo should probably update its version of minify to fix this problem.