Browsers break Korean text between any two syllables unless word-break is keep-all

Fact

Line breaking treats a Hangul syllable like a Chinese character (UAX #14 rule LB27), so under the default word-break: normal a line may end between any two syllables: 어린이 can wrap as 어 / 린이. Korean, unlike Chinese and Japanese, puts spaces between words, and word-break: keep-all limits breaks to those spaces and to punctuation. English wrapping is unchanged by it.

Why it matters

The split depends on the width, so a page that looks right on a desktop breaks words apart on a phone, in a card or in a table cell — and only on whichever line happens to end mid-word. Korean readers see it as a broken layout, the way an English reader would see "dictio / nary" with no hyphen.

How to apply

body {
  word-break: keep-all;       /* Korean wraps at spaces, like English */
  overflow-wrap: break-word;  /* a run longer than the line may still break */
}

• Always pair it with overflow-wrap: keep-all alone lets a long run with no space, such as a URL, overflow its box.
• Keep it off Chinese and Japanese. They have no spaces, so keep-all leaves only punctuation to break at and whole clauses overflow. On a page that mixes them, scope it with :lang(ko).