--- title: Polypane 30.1: Selector specificity insights, server... description: Polypane 30.1 introduces selector specificity highlighting in the elements panel, showing which parts of a CSS selector contribute to its specificity,... canonical: https://daily.dev/posts/polypane-30-1-selector-specificity-insights-server-html-validation-and-more-3ctifs0tm twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Polypane 30.1: Selector specificity insights, server HTML validation, and more | daily.dev og:description: Polypane 30.1 introduces selector specificity highlighting in the elements panel, showing which parts of a CSS selector contribute to its specificity,... og:url: https://daily.dev/posts/polypane-30-1-selector-specificity-insights-server-html-validation-and-more-3ctifs0tm og:image: https://api.daily.dev/og/posts/3ctiFs0Tm.png og:image:alt: Polypane 30.1: Selector specificity insights, server HTML validation, and more og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # Polypane 30.1: Selector specificity insights, server HTML validation, and more **[Polypane](https://daily.dev/sources/polypane)** · 5 min read · 1 upvotes · 0 comments ## Summary Polypane 30.1 introduces selector specificity highlighting in the elements panel, showing which parts of a CSS selector contribute to its specificity, including for nested selectors. The sources panel gains a toggle to compare server-sent HTML versus rendered HTML for debugging SSR issues, both validated independently. Passkey/WebAuthn support arrives on Linux via 1Password's passkey-rs library, matching existing Windows and Mac support. Other updates include gap values in the Peek tooltip, a scribble-style placeholdifier overlay, WCAG 2.2 target size checks in the accessibility panel, and an upgrade to Chromium 152, plus various fixes. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### What's new in Polypane 30.1? Polypane 30.1 adds selector specificity highlighting in the elements panel, a toggle in the sources panel to view server-sent HTML versus rendered HTML, and passkey/WebAuthn support on Linux using 1Password's passkey-rs library. It also updates to Chromium 152, adds gap values to the Peek tooltip, and checks WCAG 2.2 target size in the accessibility panel. _Track browser tooling releases like this Polypane update alongside other webdev news on daily.dev._ ### How does Polypane highlight CSS selector specificity in the elements panel? Hovering over a selector in the elements panel highlights the exact parts contributing to its specificity, including for nested CSS rules where the resolved selector is shown. The engine intelligently treats compound selectors like .card, #highspecificity as a single ID-level selector even when not present in the DOM, and drills into complex nested :is() selectors rather than treating them as one value. _Developers debugging CSS specificity conflicts can follow tooling updates like this on daily.dev._ ### Does Polypane support passkeys on Linux? Yes, Polypane 30.1 adds passkey/WebAuthn support for Linux, bringing it to parity with the existing Windows and Mac implementations. Since Linux lacks a native OS passkey backend, Polypane uses software passkeys through 1Password's passkey-rs library with a custom UI, letting developers test passkey implementations across all three platforms. _Developers testing passkey flows across platforms can track tooling changes like this on daily.dev._ --- Tags: [#css](https://daily.dev/tags/css), [#accessibility](https://daily.dev/tags/accessibility), [#polypane](https://daily.dev/tags/polypane) [View this post on daily.dev](https://daily.dev/posts/polypane-30-1-selector-specificity-insights-server-html-validation-and-more-3ctifs0tm) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"Polypane 30.1: Selector specificity insights, server HTML validation, and more","url":"https://daily.dev/posts/polypane-30-1-selector-specificity-insights-server-html-validation-and-more-3ctifs0tm","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/polypane-30-1-selector-specificity-insights-server-html-validation-and-more-3ctifs0tm"},"datePublished":"2026-08-28T11:25:05.883Z","dateModified":"2026-08-28T11:25:30.875Z","description":"Polypane 30.1 introduces selector specificity highlighting in the elements panel, showing which parts of a CSS selector contribute to its specificity,...","image":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/0541b99b533edc521c13e2f8a358c0b6?_a=AQAEuop","thumbnailUrl":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/0541b99b533edc521c13e2f8a358c0b6?_a=AQAEuop","isAccessibleForFree":true,"articleSection":"Polypane","inLanguage":"en","publisher":{"@type":"Organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180}},"author":{"@type":"Organization","name":"Polypane","logo":"https://media.daily.dev/image/upload/s--KIZm_n0x--/f_auto,q_auto/v1782646521/logos/polypane?_a=BAMAMicg0","url":"https://daily.dev/sources/polypane"},"commentCount":0,"discussionUrl":"https://daily.dev/posts/polypane-30-1-selector-specificity-insights-server-html-validation-and-more-3ctifs0tm","interactionStatistic":[{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":1},{"@type":"InteractionCounter","interactionType":{"@type":"CommentAction"},"userInteractionCount":0}],"keywords":"css,accessibility,polypane","timeRequired":"PT5M"} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://daily.dev"},{"@type":"ListItem","position":2,"name":"Polypane","item":"https://daily.dev/sources/polypane"},{"@type":"ListItem","position":3,"name":"Polypane 30.1: Selector specificity insights, server HTML validation, and more"}]} {"@context":"https://schema.org","@type":"FAQPage","@id":"https://daily.dev/posts/polypane-30-1-selector-specificity-insights-server-html-validation-and-more-3ctifs0tm#faq","mainEntity":[{"@type":"Question","name":"What's new in Polypane 30.1?","acceptedAnswer":{"@type":"Answer","text":"Polypane 30.1 adds selector specificity highlighting in the elements panel, a toggle in the sources panel to view server-sent HTML versus rendered HTML, and passkey/WebAuthn support on Linux using 1Password's passkey-rs library. 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