demo · v143
Multilingual paragraph
The real reason this property exists: getting language-specific glyph variants right inside a single paragraph that mixes multiple languages. Pick the override and watch fonts that ship multiple glyph variants (Turkish dotted-i, Polish kreska accents, Bulgarian Cyrillic forms) flip in place.
no override (default)
İstanbul · Łódź · Bucureşti · Београд · България · मराठी
font-language-override: none
İstanbul · Łódź · Bucureşti · Београд · България · मराठी
If your installed serif font ships locl rules for the chosen tag, you'll see the letterform change (the Turkish dotted-i, Polish ogonek, Bulgarian italic, etc.). If it doesn't, both sides look identical — feature works as advertised, font support is the gating factor.
the call
/* OpenType glyphs that vary by language */
.bg { font-language-override: "BGR"; } /* Bulgarian Cyrillic forms */
.pl { font-language-override: "PLK"; } /* Polish kreska accents */
.tr { font-language-override: "TRK"; } /* Turkish dotted-i */
/* Compare with the lang-attribute approach: same effect, but lang
also affects hyphenation, spellcheck, screen-reader voice, etc.
font-language-override targets ONLY glyph picking. */why this angle
The other concept compares a single string with and without override. This one shows the realistic case: a multilingual paragraph where each name should pick its locale's glyph variant — exactly the problem font designers complained about in CSSWG threads. It also shows the property's limit (font has to actually ship the variant).