demo · v136
Author overrides
Fluent is the new UA default on Windows / Linux — but the existing scrollbar-width and scrollbar-color properties still win. Four scrollers, four override strategies, side by side. Useful sanity check that your site's design system survives the v136 cosmetic refresh.
Each card uses a different author strategy. Compare visually on Windows or Linux to see Fluent baseline.
navigator.userAgentData.platform—
expected default style—
1. UA default (Fluent on Win/Linux)
/* nothing */
2. scrollbar-width: thin
.scroller { scrollbar-width: thin; }
3. scrollbar-color: branded
.scroller { scrollbar-color: blue stone; }
the code
/* Fluent is the new UA default on Windows + Linux. */
.use-ua { /* nothing */ }
.thin { scrollbar-width: thin; } /* still wins */
.branded { scrollbar-color: blue lightgray; } /* still wins */
.invisible { scrollbar-width: none; } /* hides entirely */why this angle
The sibling concept shows what Fluent looks like as the new default. This concept answers the question every existing site asks when a UA refresh ships: "Does my custom scrollbar styling still work?" Four cards, four common author choices — the answer is: yes, the existing properties keep their precedence, Fluent only changes the unstyled default.