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https://mozillazine.org

Performance

· 14 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
93
GRADE
A
FIX
1
REVIEW
2
PASS
10
INFO
1

Performance-focused optimization plan with CWV assessment, top offenders, and time estimates

Mobile Desktop
91
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
88
Accessibility Measures how accessible the page is for users with disabilities. Checks color contrast, ARIA labels, and semantic HTML.
73
Best Practices Checks for modern web development best practices including HTTPS, no console errors, and secure JavaScript.
83
SEO Measures basic SEO optimizations: meta tags, crawlability, link text, and mobile friendliness.

First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.

1.33 s

Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.

1.43 s

Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.

0 ms

Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.

0.014

Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.

1.33 s

Time to Interactive Time to Interactive — how long until the page is fully interactive and responds to user input. Under 3.8s is good.

1.43 s

Page Load Progression

375 ms
750 ms
1.1 s
1.5 s
1.9 s
2.2 s
2.6 s
3.0 s
Checks
14
10 PASS 2 REVIEW 1 FIX
D
HTTP Caching
Action
no-store (uncacheable)
FIX
no-store (uncacheable)
Info::
Cache-Control: no-store prevents all caching
Intentional for dynamic content, but increases server load for every page view.
Got: no-store
Info::
No ETag or Last-Modified header
Conditional requests (304 Not Modified) are not possible without validators.
Cache-Control

no-store

DirectiveValueMeaning
no-store—Never cache this response
B
Image Optimization
7 images, 0 KB saveable
REVIEW
7 images, 0 KB saveable
Info::
All images are well-optimized
7 images 71 KB
0 oversized -0 KB
5 legacy format
0 missing dimensions CLS risk
C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

A+
Page Weight Budget
423 KB transferred, 22 requests
PASS
423 KB transferred, 22 requests
Info::
Page weighs 453 KB (423 KB transferred)
Info::
22 HTTP requests
Info::
Estimated 0.09 g CO2 per page load
423 KB / 2.4 MB budget
423 KB transferred
22 requests
0.09 g CO2 per page load
CSS 191.2 KiB 45%
Fonts 121.8 KiB 29%
Images 70.6 KiB 17%
JavaScript 23.3 KiB 6%
HTML 7.4 KiB 2%
Other 5.6 KiB 1%
Other 2.8 KiB 1%
0 2.4 MB 4.9 MB
Under budget
A
Third-Party Impact
33% third-party, 0 ms blocking
PASS
33% third-party, 0 ms blocking
Info::
Third-party code accounts for 33% of page weight (140.0 KiB of 422.7 KiB)
Info::
Third-party blocking time is low (0 ms)
67%
33%
First-party Third-party
A+
Text Compression
All text resources are compressed
PASS
All text resources are compressed
Info::
All text resources are compressed
All text resources are properly compressed.
A+
JS Execution Cost
52ms total JS execution
PASS
52ms total JS execution
Info::
https://mozillazine.org/: 52ms CPU time

Main Thread Breakdown

Other 52% Style & Layout 20% Script Evaluation 16% Rendering 5% Script Parsing & Compilation 3%
ScriptTotalScriptingParse/CompileParty
https://mozillazine.org/52ms2ms1ms1st
A+
Font Loading
2 fonts (122 KB)
PASS
2 fonts (122 KB)
Info::
2 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

2

122 KB total

Render-blocking

0

of 2

Dominant font-display

swap

Most common across fonts

Font loading timeline
Transfer FOIT (block) FOUT (swap)
0 ms 500 ms 1.0 s 1.5 s FCP 1.3 s LCP 1.4 sdata:font/woff2;base64,d09GMgABAAAAAOykABQAAAACdZgAAOwyAAEAAAAAAAAAAAAAAAAAAAAAAAAAAAAAGoUNG4LYfByR…woff2;base64,d09GMgABAA... data:font/woff2;base64,d09GMgABAAAAAOykABQAAAACdZgAAOwyAAEAAAAAAAAAAAAAAAAAAAAAAAAAAAAAGoUNG4LYfByR… — 59.2 KiB — 13 ms — font-display: swapdata:font/woff2;base64,d09GMgABAAAAAPq4ABUAAAACTIQAAPo7AAFmqAAAAAAAAAAAAAAAAAAAAAAAAAAAGokqG4Hrchya…woff2;base64,d09GMgABAA... data:font/woff2;base64,d09GMgABAAAAAPq4ABUAAAACTIQAAPo7AAFmqAAAAAAAAAAAAAAAAAAAAAAAAAAAGokqG4Hrchya… — 62.7 KiB — 16 ms — font-display: swap
woff2;base64,d09GMgABAA... woff2 swap
Size 59 KB
Load time 13 ms
Start 1.4 s
Risk FOUT — text flashes from fallback to web font
woff2;base64,d09GMgABAA... woff2 swap
Size 63 KB
Load time 16 ms
Start 1.4 s
Risk FOUT — text flashes from fallback to web font
Optimization checklist
  • Preload critical fonts (priority=high)
  • Use woff2 format for all fonts
  • Set font-display to swap, optional, or fallback
  • Subset large fonts (≤100 KB each)
A+
JS Bundles
6 scripts, 0 KB unused
PASS
6 scripts, 0 KB unused
0 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://mozillazine.org/.within.website/x/cmd/anubis/static/js/main.mjs?cacheBuster=1.25.06 KB—✓1st
https://mozillazine.org/.within.website/x/cmd/anubis/static/js/worker/sha256-webcrypto.mjs?cacheBuster=1.25.00 KB—✓1st
https://mozillazine.org/.within.website/x/cmd/anubis/static/js/worker/sha256-webcrypto.mjs?cacheBuster=1.25.00 KB—✓1st
http://www.google-analytics.com/urchin.js0 KB—✓3rd
https://ssl.google-analytics.com/ga.js17 KB—✓3rd
http://pagead2.googlesyndication.com/pagead/show_ads.js0 KB—✓3rd
A+
Resource Caching
All resources properly cached
PASS
All resources properly cached
Info::
No caching issues found
All static resources have appropriate caching headers.
A+
Critical Rendering Path
No render-blocking resources
PASS
No render-blocking resources
Info::
No render-blocking resources detected
A+
Resource Hints
No optimization needed
PASS
No optimization needed
Info::
No resource hint issues
A+
Page Weight Inventory
22 resources · 423 KB · 0 KB savings available
PASS
22 resources · 423 KB · 0 KB savings available
Info::
Within 1MB page-weight target
Got: 423 KB
Info::
7 third-party resources (33% of weight)
22 resources · 422.7 KiB · 7 third-party Within 1MB page-weight target
CSS 45% · 191.2 KiB
Font 29% · 121.8 KiB
Image 17% · 72.7 KiB
JavaScript 6% · 23.3 KiB
Document 2% · 8.0 KiB
Other 1% · 5.6 KiB
Network Waterfall
22 requests over 2692ms
INFO
0 ms 500 ms 1.0 s 1.5 s 2.0 s 2.5 s FCP 1.3 s LCP 1.4 shttps://mozillazine.org// https://mozillazine.org/ — 200 — 2.5 KiB — 528 ms — h2https://mozillazine.org/.within.website/x/xess/xess.min.css?cachebuster=1.25.0/.within.website/x/xess/xess.min.cs... https://mozillazine.org/.within.website/x/xess/xess.min.css?cachebuster=1.25.0 — 200 — 190.4 KiB — 879 ms — h2https://mozillazine.org/.within.website/x/cmd/anubis/static/img/pensive.webp?cacheBuster=1.25.0/.within.website/x/cmd/anubis/stati... https://mozillazine.org/.within.website/x/cmd/anubis/static/img/pensive.webp?cacheBuster=1.25.0 — 200 — 28.3 KiB — 527 ms — h2https://mozillazine.org/.within.website/x/cmd/anubis/static/img/happy.webp?cacheBuster=1.25.0/.within.website/x/cmd/anubis/stati... https://mozillazine.org/.within.website/x/cmd/anubis/static/img/happy.webp?cacheBuster=1.25.0 — 200 — 30.0 KiB — 877 ms — h2https://mozillazine.org/.within.website/x/cmd/anubis/static/js/main.mjs?cacheBuster=1.25.0/.within.website/x/cmd/anubis/stati... https://mozillazine.org/.within.website/x/cmd/anubis/static/js/main.mjs?cacheBuster=1.25.0 — 200 — 5.8 KiB — 702 ms — h2https://mozillazine.org/.within.website/x/cmd/anubis/static/locales/en.json/.within.website/x/cmd/anubis/stati... https://mozillazine.org/.within.website/x/cmd/anubis/static/locales/en.json — 200 — 5.6 KiB — 347 ms — h2data:font/woff2;base64,d09GMgABAAAAAOykABQAAAACdZgAAOwyAAEAAAAAAAAAAAAAAAAAAAAAAAAAAAAAGoUNG4LYfByR…data:font/woff2;base64,d09GMgABAAAA... data:font/woff2;base64,d09GMgABAAAAAOykABQAAAACdZgAAOwyAAEAAAAAAAAAAAAAAAAAAAAAAAAAAAAAGoUNG4LYfByR… — 200 — 59.2 KiB — 13 ms — datadata:font/woff2;base64,d09GMgABAAAAAPq4ABUAAAACTIQAAPo7AAFmqAAAAAAAAAAAAAAAAAAAAAAAAAAAGokqG4Hrchya…data:font/woff2;base64,d09GMgABAAAA... data:font/woff2;base64,d09GMgABAAAAAPq4ABUAAAACTIQAAPo7AAFmqAAAAAAAAAAAAAAAAAAAAAAAAAAAGokqG4Hrchya… — 200 — 62.7 KiB — 16 ms — datahttps://mozillazine.org/favicon.ico/favicon.ico https://mozillazine.org/favicon.ico — 200 — 2.1 KiB — 179 ms — h2https://mozillazine.org/.within.website/x/cmd/anubis/static/js/worker/sha256-webcrypto.mjs?cacheBuster=1.25.0/.within.website/x/cmd/anubis/stati... https://mozillazine.org/.within.website/x/cmd/anubis/static/js/worker/sha256-webcrypto.mjs?cacheBuster=1.25.0 — 200 — 112 B — 187 ms — h2https://mozillazine.org/.within.website/x/cmd/anubis/static/js/worker/sha256-webcrypto.mjs?cacheBuster=1.25.0/.within.website/x/cmd/anubis/stati... https://mozillazine.org/.within.website/x/cmd/anubis/static/js/worker/sha256-webcrypto.mjs?cacheBuster=1.25.0 — 200 — 0 B — 186 ms — h2https://mozillazine.org/.within.website/x/cmd/anubis/api/pass-challenge?id=019db29a-eada-7495-8bfc-246e9b06a4c5&response=00007e8ca3272850a4bc3c3093f03b255a13b93947073ff1a63e2fa3a4af40d8&nonce=24802&redir=https%3A%2F%2Fmozillazine.org%2F&elapsedTime=367/.within.website/x/cmd/anubis/api/p... https://mozillazine.org/.within.website/x/cmd/anubis/api/pass-challenge?id=019db29a-eada-7495-8bfc-246e9b06a4c5&response=00007e8ca3272850a4bc3c3093f03b255a13b93947073ff1a63e2fa3a4af40d8&nonce=24802&redir=https%3A%2F%2Fmozillazine.org%2F&elapsedTime=367 — 302 — 661 B — 177 ms — h2https://mozillazine.org// https://mozillazine.org/ — 200 — 4.8 KiB — 179 ms — h2https://mozillazine.org/style/smallfront.css/style/smallfront.css https://mozillazine.org/style/smallfront.css — 200 — 865 B — 178 ms — h2https://mozillazine.org/image/new/title.gif/image/new/title.gif https://mozillazine.org/image/new/title.gif — 200 — 1.1 KiB — 179 ms — h2http://www.google-analytics.com/urchin.jswww.google-analytics.com/urchin.js http://www.google-analytics.com/urchin.js — -1 — 0 B — 0 ms — https://ssl.google-analytics.com/ga.jsssl.google-analytics.com/ga.js https://ssl.google-analytics.com/ga.js — 200 — 17.4 KiB — 76 ms — h2http://pagead2.googlesyndication.com/pagead/show_ads.jspagead2.googlesyndication.com/pagea... http://pagead2.googlesyndication.com/pagead/show_ads.js — -1 — 0 B — 0 ms — https://mozillazine.org/image/default/sky.png/image/default/sky.png https://mozillazine.org/image/default/sky.png — 200 — 8.6 KiB — 178 ms — h2https://mozillazine.org/image/default/blimp.png/image/default/blimp.png https://mozillazine.org/image/default/blimp.png — 200 — 1.7 KiB — 179 ms — h2https://ssl.google-analytics.com/r/__utm.gif?utmwv=5.7.2&utms=1&utmn=1648600083&utmhn=mozillazine.org&utmcs=windows-1252&utmsr=800x600&utmvp=1350x940&utmsc=24-bit&utmul=en-us&utmje=0&utmfl=-&utmdt=mozillaZine&utmhid=1423066118&utmr=0&utmp=%2F&utmht=1776817992521&utmac=UA-32170104-1&utmcc=__utma%3D4421167.487574507.1776817993.1776817993.1776817993.1%3B%2B__utmz%3D4421167.1776817993.1.1.utmcsr%3D(direct)%7Cutmccn%3D(direct)%7Cutmcmd%3D(none)%3B&utmjid=1027882639&utmredir=1&utmu=qBAAAAAAAAAAAAAAAAAAAAAE~ssl.google-analytics.com/r/__utm.gi... https://ssl.google-analytics.com/r/__utm.gif?utmwv=5.7.2&utms=1&utmn=1648600083&utmhn=mozillazine.org&utmcs=windows-1252&utmsr=800x600&utmvp=1350x940&utmsc=24-bit&utmul=en-us&utmje=0&utmfl=-&utmdt=mozillaZine&utmhid=1423066118&utmr=0&utmp=%2F&utmht=1776817992521&utmac=UA-32170104-1&utmcc=__utma%3D4421167.487574507.1776817993.1776817993.1776817993.1%3B%2B__utmz%3D4421167.1776817993.1.1.utmcsr%3D(direct)%7Cutmccn%3D(direct)%7Cutmcmd%3D(none)%3B&utmjid=1027882639&utmredir=1&utmu=qBAAAAAAAAAAAAAAAAAAAAAE~ — 200 — 365 B — 27 ms — h2https://ssl.google-analytics.com/__utm.gif?utmwv=5.7.2&utms=2&utmn=943380698&utmhn=mozillazine.org&utmcs=windows-1252&utmsr=800x600&utmvp=1350x940&utmsc=24-bit&utmul=en-us&utmje=0&utmfl=-&utmdt=mozillaZine&utmhid=1423066118&utmr=0&utmp=%2F&utmht=1776817992522&utmac=UA-21953982-1&utmcc=__utma%3D4421167.487574507.1776817993.1776817993.1776817993.1%3B%2B__utmz%3D4421167.1776817993.1.1.utmcsr%3D(direct)%7Cutmccn%3D(direct)%7Cutmcmd%3D(none)%3B&utmjid=&utmmt=1&utmu=qBAAAAAAAAAAAAAAAAAAAAAE~ssl.google-analytics.com/__utm.gif?... https://ssl.google-analytics.com/__utm.gif?utmwv=5.7.2&utms=2&utmn=943380698&utmhn=mozillazine.org&utmcs=windows-1252&utmsr=800x600&utmvp=1350x940&utmsc=24-bit&utmul=en-us&utmje=0&utmfl=-&utmdt=mozillaZine&utmhid=1423066118&utmr=0&utmp=%2F&utmht=1776817992522&utmac=UA-21953982-1&utmcc=__utma%3D4421167.487574507.1776817993.1776817993.1776817993.1%3B%2B__utmz%3D4421167.1776817993.1.1.utmcsr%3D(direct)%7Cutmccn%3D(direct)%7Cutmcmd%3D(none)%3B&utmjid=&utmmt=1&utmu=qBAAAAAAAAAAAAAAAAAAAAAE~ — 200 — 438 B — 24 ms — h2
HTML JavaScript CSS Images Fonts XHR/Fetch Other
All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.

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