Load Pico CSS non-render-blocking via preload+swap - #165
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Lighthouse flagged the jsDelivr-hosted Pico CSS as the largest render-blocking request (~759ms estimated savings). Rather than vendoring the file into the repo, use the standard preload+onload swap pattern (with a <noscript> fallback) so it downloads without blocking the parser, then applies as a stylesheet once loaded. Note: since Pico is the site's primary CSS framework (not a minor addition), this trades render-blocking for a brief flash of unstyled content while the swap completes - negligible on a fast connection, more visible on a slow one. Verified locally: no console errors, the link's rel correctly flips to "stylesheet", and Pico's theme (colors, fonts, grid) is fully applied post-load. Fixes #157 Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
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Summary
pico.pumpkin.min.css(loaded from jsDelivr) as the largest render-blocking request, ~759ms estimated savings.rel="preload"+onloadswap pattern (with a<noscript>fallback) so the browser fetches it without blocking HTML parsing, then applies it as a stylesheet once it arrives.Trade-off to be aware of
Pico is this site's primary CSS framework, not a minor addition —
custom.cssbuilds on its classes/variables. Making it non-blocking means the page can render briefly unstyled before the swap fires (a real flash-of-unstyled-content, not just a cosmetic nit). On a fast connection this window is very short; on a slow/high-latency connection it will be more visible. Recommend reviewers check this with Chrome DevTools network throttling (e.g. "Slow 4G") before merging, to confirm the trade-off is acceptable.Fixes #157
Test plan
<link>'srelcorrectly flips frompreloadtostylesheeton load🤖 Generated with Claude Code