(POC) Theme Showcase: Style selection in the theme details page

[taipeicoder]

Proposed Changes

Testing Instructions

Pre-merge Checklist

• Has the general commit checklist been followed? (PCYsg-hS-p2)
• Have you written new tests for your changes?
• Have you tested the feature in Simple (P9HQHe-k8-p2), Atomic (P9HQHe-jW-p2), and self-hosted Jetpack sites (PCYsg-g6b-p2)?
• Have you checked for TypeScript, React or other console errors?
• Have you used memoizing on expensive computations? More info in Memoizing with create-selector and Using memoizing selectors and Our Approach to Data
• Have we added the "[Status] String Freeze" label as soon as any new strings were ready for translation (p4TIVU-5Jq-p2)?
• For changes affecting Jetpack: Have we added the "[Status] Needs Privacy Updates" label if this pull request changes what data or activity we track or use (p4TIVU-ajp-p2)?

Related to #

[github-actions]

Calypso Live (direct link)

https://calypso.live?image=registry.a8c.com/calypso/app:build-56016

Jetpack Cloud live (direct link)

https://calypso.live?image=registry.a8c.com/calypso/app:build-56016&env=jetpack

[matticbot]

Here is how your PR affects size of JS and CSS bundles shipped to the user's browser:

App Entrypoints (~89 bytes added 📈 [gzipped])

name                   parsed_size           gzip_size
entry-stepper               +492 B  (+0.0%)      +87 B  (+0.0%)
entry-main                  +492 B  (+0.0%)      +83 B  (+0.0%)
entry-login                 +384 B  (+0.0%)      +84 B  (+0.0%)
entry-domains-landing       +384 B  (+0.1%)      +84 B  (+0.1%)
entry-browsehappy           +384 B  (+0.4%)      +84 B  (+0.3%)
entry-gutenboarding         +371 B  (+0.0%)      +87 B  (+0.0%)

Common code that is always downloaded and parsed every time the app is loaded, no matter which route is used.

Sections (~4207 bytes added 📈 [gzipped])

name   parsed_size           gzip_size
theme     +13141 B  (+2.7%)    +4207 B  (+2.9%)

Sections contain code specific for a given set of routes. Is downloaded and parsed only when a particular route is navigated to.

Async-loaded Components (~2261 bytes added 📈 [gzipped])

name                                                                 parsed_size           gzip_size
async-load-automattic-design-preview-src-components-style-variation   +1164747 B    (new)  +348886 B    (new)
async-load-automattic-design-preview                                      +618 B  (+0.1%)      +63 B  (+0.0%)
async-load-pattern-list-renderer                                           -13 B  (-0.0%)      +17 B  (+0.0%)
async-load-pattern-large-preview                                           -13 B  (-0.0%)      +15 B  (+0.0%)
async-load-pattern-assembler-container                                     -13 B  (-0.0%)      +19 B  (+0.0%)

React components that are loaded lazily, when a certain part of UI is displayed for the first time.

Legend

What is parsed and gzip size?

Parsed Size: Uncompressed size of the JS and CSS files. This much code needs to be parsed and stored in memory.
Gzip Size: Compressed size of the JS and CSS files. This much data needs to be downloaded over network.

Generated by performance advisor bot at iscalypsofastyet.com.

[taipeicoder]

Closing in favor of #73277.