--- 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 new features are included in Polypane 30.1? Polypane 30.1 adds selector specificity highlighting in the elements panel, a toggle in the sources panel to switch between server-sent and rendered HTML, and passkey/WebAuthn support on Linux using 1Password's passkey-rs library. It also displays gap values in the Peek tooltip and runs on Chromium 152. _Track browser tooling releases like Polypane's alongside the rest of your webdev stack on daily.dev._ ### How does Polypane highlight CSS selector specificity for nested selectors? Hovering over a nested CSS selector in Polypane's elements panel highlights the resolved parent selector parts that contribute to specificity, and it correctly treats compound selectors like .card, #highspecificity as counting as a single ID selector even when that ID isn't present in the DOM. Complex wrapped selectors using :is() are drilled down into rather than counted as one value. _Developers debugging CSS specificity conflicts can follow tooling updates like this on daily.dev._ ### How does Polypane implement passkey support on Linux without a platform passkey backend? Polypane uses software passkeys through 1Password's passkey-rs library on Linux, since unlike Windows and Mac, Linux lacks a native operating-system backend for passkeys/WebAuthn. This required a custom UI in Polypane, but it brings feature parity across Windows, Mac, and Linux for testing passkey implementations. _Anyone testing passkey/WebAuthn flows across platforms can track tooling like this on daily.dev._ ## Similar posts on daily.dev - [Polypane 30: Playgrounds, Side Panel extension API, updated video recording and Chromium 152](https://daily.dev/posts/polypane-30-playgrounds-side-panel-extension-api-updated-video-recording-and-chromium-152-cuj2wsicc) · Polypane · 2 upvotes · 1 comments --- 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":"2026-09-14T06:31:35.827Z","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 new features are included 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 switch between server-sent and rendered HTML, and passkey/WebAuthn support on Linux using 1Password's passkey-rs library. 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