Performance

· 27 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.

SCORE

GRADE

FIX

REVIEW

PASS

INFO

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

Mobile Desktop

Performance

Accessibility

Best Practices

SEO

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

6.16 s

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

12.15 s

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

418 ms

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

0.338

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

10.48 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.

12.32 s

Page Load Progression

1.0 s

2.1 s

3.1 s

4.2 s

5.2 s

6.2 s

7.3 s

8.3 s

Checks

15 PASS 4 REVIEW 5 FIX

Page Weight Budget

Action

3.1 MB transferred, 440 requests

FIX

3.1 MB transferred, 440 requests

Page weighs 5.5 MB (3.1 MB transferred)

Images are 1.1 MB — compress or use modern formats

Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.

Got: 1.1 MB

JavaScript is 620 KB — consider code splitting or lazy loading

Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.

Got: 620 KB

440 HTTP requests — consider bundling or reducing

Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.

Estimated 0.66 g CO2 per page load

3.1 MB transferred

440 requests

0.66 g CO2 per page load

Images 1.1 MiB 36%

Other 946.7 KiB 29%

JavaScript 619.9 KiB 19%

HTML 276.2 KiB 9%

Fonts 77.9 KiB 2%

Other 56.7 KiB 2%

Other 50.1 KiB 2%

CSS 37.1 KiB 1%

Other 9.7 KiB 0%

Other 0 B 0%

0 2.4 MB 4.9 MB

Over budget

Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.

Why this matters

Image bandwidth is high — modern formats (WebP/AVIF) and resizing typically cut it 50%+.

Source: web.dev

Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.

Why this matters

JavaScript bundle is large — code-split routes and lazy-load off-screen components to defer.

Source: web.dev

Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.

Why this matters

High HTTP request count — bundling, sprite-ing, and HTTP/2 server push can reduce per-request overhead.

Source: web.dev

Third-Party Impact

Action

100% third-party, 0 ms blocking

FIX

100% third-party, 0 ms blocking

Third-party code accounts for 100% of page weight (3.1 MiB of 3.1 MiB)

Third-party blocking time is low (0 ms)

100%

First-party Third-party

JS Execution Cost

Action

9892ms total JS execution

FIX

9892ms total JS execution

https://www.mossandmolt.com/: 5797ms CPU time

Unattributable: 1525ms CPU time

https://www.mossandmolt.com/cdn/wpm/b78841ebdw6fd1...: 787ms CPU time

https://cdn.shopify.com/extensions/01a18241-b12a-7...: 777ms CPU time

https://cdn.shopify.com/storefront/web-components/...: 191ms CPU time

Third-party scripts: 8367ms (85% of total)

Main Thread Breakdown

Style & Layout 34% Script Evaluation 29% Other 29%

Script	Total	Scripting	Parse/Compile	Party
https://www.mossandmolt.com/	5797ms	1019ms	134ms	3rd
Unattributable	1525ms	108ms	0ms	1st
https://www.mossandmolt.com/cdn/wpm/b78841ebdw6fd1eda2peb7ac126m6aaa99abm.js	787ms	448ms	28ms	3rd
https://cdn.shopify.com/extensions/01a18241-b12a-793d-aab3-0689dd4e6842/judgeme-833/assets/loader.js	777ms	386ms	1ms	3rd
https://cdn.shopify.com/storefront/web-components/account.js	191ms	57ms	0ms	3rd
https://cdn.shopify.com/shopifycloud/shop-js/modules/v2/chunk.register_BsQ6fabn.esm.js	177ms	117ms	0ms	3rd
https://www.mossandmolt.com/cdn/s/trekkie.storefront.387430da5919a2f9b410f0ffaf5b70216a61abfb.min.js	170ms	150ms	12ms	3rd
https://www.mossandmolt.com/cdn/shopifycloud/storefront/assets/storefront/remote_product_tracking-91d95044.js	131ms	50ms	4ms	3rd
https://www.mossandmolt.com/cdn/shopifycloud/perf-kit/shopify-perf-kit-3.11.0.min.js	119ms	106ms	10ms	3rd
https://www.mossandmolt.com/cdn/shop/t/18/assets/slideshow.js?v=123600913920212518311792301455	110ms	25ms	0ms	3rd

Showing top 10 of 12 scripts

Page Weight Inventory

Action

440 resources · 3.1 MB · 38 KB savings available

FIX

440 resources · 3.1 MB · 38 KB savings available

Page weight 3.1 MB exceeds 1 MB target by 2.1 MB

Got: 3.1 MB Expected: ≤ 1 MB

438 third-party resources (100% of weight)

1 resources over 200KB

440 resources · 3.1 MiB · 438 third-party 2.1 MiB over 1MB target

JavaScript 50% · 1.6 MiB

Image 36% · 1.1 MiB

Document 9% · 301.0 KiB

Font 2% · 77.9 KiB

CSS 1% · 42.4 KiB

Other 1% · 41.0 KiB

~37.6 KiB of savings available

Remove unused JavaScript: 37.6 KiB

#	Resource	Type	Size	Cache	Unused	3rd party	Issues

440 resources			3.1 MiB

HTTP Caching

Action

No cache headers

FIX

No cache headers

No Cache-Control header found

Browsers will use heuristic caching, which can be unpredictable. Set explicit cache headers.

No Cache-Control header

Adding a Cache-Control header can significantly improve repeat-visit performance.

Document Compression

Action

Document response served uncompressed

REVIEW

Document response served uncompressed

Main HTML response has no Content-Encoding (uncompressed)

The main HTML document is served without compression. The Text Compression section above lists the broader picture; for the main response specifically, even gzip would shave ~70-80% off most text payloads.

Main HTML Cache-Control

No Cache-Control header on main HTML response

REVIEW

No Cache-Control header on main HTML response

Main HTML response has no Cache-Control header

Without an explicit Cache-Control, browsers fall back to heuristic caching (~10% of Last-Modified age). Set `Cache-Control: no-cache` or `max-age=300` for HTML to control freshness explicitly -- prevents stale auth state and SPA shell drift.

Server-Timing Observability

No Server-Timing header found

REVIEW

No Server-Timing header found

Server-Timing exposes backend timing breakdowns to browser DevTools (e.g., `db: 45ms; render: 120ms; cache: 2ms`). Useful for diagnosing slow pages without backend log access. Most modern frameworks (Next.js, Cloudflare Workers, Fastly) emit it automatically; absence on a managed platform usually means telemetry headers are stripped at the edge.

CSS Performance Depth

2 CSS depth issue(s) detected

REVIEW

2 CSS depth issue(s) detected

22 render-blocking stylesheet(s) -- recommended: <=3

Each `<link rel="stylesheet">` without a non-blocking `media` attribute holds up the first paint. Browsers download all of them before painting any content. Consolidate into 1-2 critical-path stylesheets; defer non-critical CSS via `<link rel="stylesheet" media="print" onload="this.media='all'">` or via the loadCSS pattern; inline above-the-fold CSS in `<style>` to short-circuit the request entirely.

1 `@font-face` rule(s) without `font-display` -- causes FOIT

An `@font-face` rule without `font-display` causes Flash of Invisible Text (FOIT): the browser hides the styled text for up to 3 seconds while the custom font downloads, then either swaps to fallback (Chrome / Firefox) or stays invisible (older Safari). Add `font-display: swap` (shows fallback immediately, swaps in the custom font when ready) or `font-display: optional` (uses fallback if the font isn't ready in 100ms; never causes visible swap). Either eliminates FOIT outright.

A+

Text Compression

All text resources are compressed

PASS

All text resources are compressed

All text resources are properly compressed.

A+

Image Optimization

37 images, 0 KB saveable

PASS

37 images, 0 KB saveable

All images are well-optimized

37 images 1.1 MB

0 oversized -0 KB

1 legacy format

0 missing dimensions CLS risk

A+

Font Loading

6 fonts (78 KB)

PASS

6 fonts (78 KB)

6 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

78 KB total

Render-blocking

of 6

Dominant font-display

swap

Most common across fonts

Font loading timeline

Transfer FOIT (block) FOUT (swap)

inter_n5.d7101d5e168594... woff2 swap

Size 0 KB

Load time 3 ms

Start 417 ms