Chrome 154 enforces CORS and Local Network Access for Background Fetch targets on localhost and the LAN, the one item here that needs work before the September 22 stable. The CSS additions are branch work, and text decoration insets retire gradient underline hacks.
Chrome 154 entered beta on September 2, 2026, with stable due September 22. The only item requiring work this week is Background Fetch, which now enforces CORS and requires Local Network Access permission for local and loopback targets. Enterprise opt-outs exist: LocalNetworkAccessRestrictionsTemporaryOptOut and LoopbackNetworkAllowedForUrls.
Chrome 154's CSS additions are branch work. text-decoration-inset controls how far underlines, overlines, and line-through decorations inset from or extend past text run edges, and retires the background-gradient underline hacks. text-decoration-skip-spaces keeps decorations from being drawn under spaces. scroll-marker-group gains a tabs mode beside the default links, for a CSS-only carousel whose markers must announce as a tab list; links stays the default, so existing markup needs no change.
Priority matters more than volume. A Background Fetch failure surfaces in a service worker, off the critical path, so a CORS rejection or a missing permission shows up as a sync that quietly stops delivering rather than a loud error. The CSS items cannot break production and can wait past September 22.
If you fetch from a service worker against localhost or a LAN address, confirm the CORS headers and permission prompts before September 22; if your release has no room, request an opt-out policy. Pull text-decoration-inset into a branch and delete the gradient hacks it replaces.
Firefox 154 is the last gap: text-box and the sibling functions now work in every major engine, so you can delete the JavaScript and utility-class hacks doing their job.
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Chrome 152 stable ships a standard CPU performance tier API, a network allowlist header, and CSSPseudoElement targets for backdrop clicks and mid-flight view transitions.
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CSS Gap Decorations let you draw rules and borders in the gaps between Grid, Flexbox, and multi-column items. `column-rule` and `row-rule` now work with inset, visibility, and color properties, replacing hacky background tricks.
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