Why it matters
Lighthouse's simulated-throttling score is a deterministic cross-machine summary of load performance.
How to fix it
Work through the lab metrics and the Lighthouse opportunities listed with this report.
References
More performance rules
void perf reports 25 rules in this category. Core Web Vitals and bytes: LCP, CLS, TBT, TTFB, JavaScript, CSS, fonts, images, caching and compression, measured as the median of several runs on a throttled mobile and a desktop profile.
images-missing-dimensionsImages without width/height or aspect-ratiorender-blockingRender-blocking resources delay first paintno-text-compressionText resources are served uncompressedcache-headersHashed static assets are not cached long-termthird-party-heavyHeavy third-party footprintdom-sizeDOM is very largebfcache-blockedPage is not eligible for the back/forward cachelighthouse-auditLighthouse flagged an opportunity