Why is hyphenation not working with lang en

Question

What is wrong with this code that hyphenations don't work for lang="en"?

h1 {
  font-size: 2em;
  hyphens: auto;
}

div {
  max-width:200px;
  background: aqua;
}

<div>
  <h1 lang="en">Kindofverylongheadlineevenbiggerthanimagined</h1>
  <h1 lang="en">Internationalization</h1>
  <h1 lang="de">Kindofverylongheadlineevenbiggerthanimagined</h1>
</div>

Harden

Hyphenation rules are language-specific. In HTML, the language is determined by the lang attribute, and browsers will hyphenate only if this attribute is present and the appropriate hyphenation dictionary is available. MDN – Contraception

If look at this article it says a couple of things: 1. You must specify a language using the lang HTML attribute to guarantee that automatic hyphenation is applied in that language. 2. browsers will hyphenate only if this attribute is present and the appropriate hyphenation dictionary is available 3. It is possible that you are setting correct bounds for your text container. – Robbie

Note all the notes regarding browser support on caniuse.com's support listing for the property. – Lejeune

@Robbie please don't use code formatting for emphasis or quoting. Use it for code. – Lejeune

Wondering why I see the German text hyphenated but not the English – Cariole

Was just noticing that. – Elvieelvin

Duplicate? – Contraception

Does this answer your question? Why hyphens don't work with inner <span>? – Elvieelvin

I voted duplicate and tried some of the answers there, but they didn't then, and still don't seem to fix the problem. Win/Firefox and Chrome. – Elvieelvin