Boost: Ensure LCP Image comparison ignores HTML encoding

[LiamSarsfield]

Fixes HOG-124: Make LCP optimization and Image CDN play nice with each other

Proposed changes:

• Ensures that the image HTML from the $buffer and the HTML from the Cloud are compared with the same appropriate characters.

Other information:

• Have you written new tests for your changes, if applicable?
• Have you checked the E2E test CI results, and verified that your changes do not break them?
• Have you tested your changes on WordPress.com, if applicable (if so, you'll see a generated comment below with a script to run)?

Jetpack product discussion

Does this pull request change what data or activity we track or use?

Testing instructions:

Prerequisites:

• Ensure https://github.com/Automattic/boost-cloud/pull/688 is checked out within Boost Cloud
• Latest Jetpack Boost Developer plugin installed and activated.
• Your local Boost Cloud is connected to your local WP instance.
• At least one Cornerstone Page set.
• Boost Feature Flag enabled within the install (JETPACK_BOOST_ALPHA_FEATURES)
• LCP Optimization feature enabled.
• Image CDN is enabled.

Instructions

1. Optimize the LCP, and wait for it to be completed.
2. Visit the optimized page
3. Check that the LCP image receives the LCP optimization attributes, such as:
   • fetchpriority="high"
   • loading="eager"
4. Inspect the network tab to ensure Image CDN URLs are applied
5. Before this fix: LCP images with HTML entity differences would not be matched and optimized.
6. After this fix: LCP images are properly matched and optimized regardless of HTML entity encoding variations.

[github-actions]

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Boost plugin:

• Next scheduled release: May 29, 2025

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[jp-launch-control]

Code Coverage Summary

Coverage changed in 1 file.

File	Coverage	Δ%	Δ Uncovered
projects/plugins/boost/app/modules/optimizations/lcp/class-lcp-optimize-img-tag.php	0/82 (0.00%)	0.00%	3 ❤️‍🩹

Full summary · PHP report · JS report