Covers the PreviewUrlModifier extension point in Website Builder. Use when a user wants to inject custom query parameters into live preview URLs — e.g. signed tokens, tenant identifiers, feature flags — from their Webiny project. Handles the full registration pattern: implementing the interface, wiring via createFeature + RegisterFeature, and registering via webiny.config.tsx. Supports async modifier methods (e.g. remote token fetch).
$npx -y skills add webiny/webiny-js --skill wb-preview-url-modifierInstalls into the current project.
Run `npx skills use "https://github.com/webiny/webiny-js" --skill "webiny/webiny-js/wb-preview-url-modifier"` and follow the generated skill instructions now. Read its complete output, redirecting it to a temporary file first if necessary. Resolve relative paths from the supporting-files directory it provides.
Use the skills in "https://github.com/webiny/webiny-js" that are relevant to the current task. Run `npx skills add "https://github.com/webiny/webiny-js"` and select the relevant skills, then follow their instructions.