hyphenate-limit-chars replaces and extends hyphenate-limit-{before,after} <http://dev.w3.org/cvsweb/~checkout~/csswg/css3-text/Overview.html?rev=1.181;content-type=text%2Fhtml#hyphenate-char-limits>
The current spec of 'hyphenate-limit-chars': https://drafts.csswg.org/css-text-4/#propdef-hyphenate-limit-chars