Problem

Static-site header conversion currently loses two related semantic surfaces:

• constrained search forms are recognized but preserved as core/html, so provider-specific search endpoints and adjacent icon toggles do not become functional native WordPress search
• list-shaped navigation selectors such as ul.site-menu > li and ul.site-menu > li a are not fully retargeted to the runtime markup emitted by core/navigation, losing menu spacing and typography

The four-page mrfoxtalbot.weebly.com parity fixture demonstrates both gaps. Its header uses a GET /apps/search form with a single q input plus adjacent search/open/close controls, and desktop navigation styles carried by list/item/anchor selectors.

Proposed Direction

1. Detect a constrained search cluster with one GET query input and optional adjacent search trigger controls.
2. Convert it to dynamic core/search, using buttonPosition: button-only and buttonUseIcon: true for expandable icon-search patterns.
3. Treat conversion as an intentional migration from provider-specific search endpoints to native WordPress search (s).
4. Project accepted source form/input/button selectors onto core search runtime classes.
5. Retarget source navigation list/item/link selectors onto the corresponding core/navigation runtime structure while preserving combinators, states, media rules, and specificity.
6. Preserve complex/runtime-dependent search and filter forms as raw HTML.

Acceptance

• eligible header search clusters render functional native WordPress search with an icon trigger
• arbitrary forms remain losslessly preserved
• source navigation typography, casing, item spacing, hover treatment, and responsive rules survive conversion
• generated blocks validate in the editor
• existing transformer contracts and parity fixtures pass
• the four-page Weebly replay shows the repaired header on Home, Services, Team, and Contact

Evidence

• Search detection currently returns HTML preservation: php-transformer/src/HtmlToBlocks/HtmlTransformer.php:7068-7112
• Standalone constrained search already emits core/search: php-transformer/src/HtmlToBlocks/HtmlTransformer.php:7117-7163
• Existing header contract locks the current gap: php-transformer/tests/contract/run.php:1611-1620
• WordPress core provides icon-only expandable search through the Interactivity API: wp-includes/blocks/search.php

AI assistance

OpenAI gpt-5.6-sol through OpenCode was used to investigate current behavior, inspect the Weebly fixture and WordPress core implementation, and draft this issue. Chris Huber remains responsible for scope and implementation decisions.