Content Security Policy in TYPO3 v13 and v14
A CSP header set by hand in .htaccess fights with the one TYPO3 already sends for the backend. Use the core API instead: feature flags, csp.yaml per site, extension mutations and nonces.
Core Web Vitals on a TYPO3 site: images, fonts and CSS
Most LCP and layout shift problems on TYPO3 pages come from oversized images, late fonts and blocking CSS. Fixes with f:image, srcset, preload and font-display, and how to measure.