Navigation redirect

Entitlement: navigationRedirect. Configuration: internal.navigation_redirect, an object mapping URL patterns to target strings. No JavaScript API is required.

Configure mappings

{
  "internal": {
    "navigation_redirect": {
      "https://example.com/old*": "https://example.org/",
      "https://example.com/blank*": ""
    }
  }
}

Merge into the EP, sign if required, and restart. Navigating to https://example.com/old-page should load https://example.org/. An empty target means about:blank, not a network cancellation error.

Patterns match the full URL and are case-sensitive. * matches zero or more characters; ? matches zero or one character. Escape a literal ? with a backslash: a JSON mapping key such as "https://example.com/old\\?mode=*" matches the query separator literally. This is not regex or extension match-pattern syntax.

Targets are fixed URLs, not substitution templates; capture groups are not expanded. Non-string entries and invalid targets are skipped. Avoid overlapping mappings and redirect cycles rather than relying on JSON insertion order as a priority mechanism.

Replace the new-tab page

Install a Provision plugin named my-plugin containing index.html, then configure:

{
  "internal": {
    "navigation_redirect": {
      "chrome://newtab/": "provision-extension://my-plugin/index.html"
    }
  }
}

Use chrome://newtab/, including the trailing slash, not chrome://new-tab-page/. In a Provision target, use the installed plugin's directory name and an existing page path; you do not need to hardcode an extension ID.

This avoids an extension-wide chrome_url_overrides.newtab manifest override when only selected EP-configured instances should use your page.

Scope and boundaries

Rules apply to supported chrome:// pages and top-level navigations, not iframe, image, or fetch requests. HTTP redirect destinations are not re-evaluated by these rules. If a top-level form submission matches, the replacement opens as a new navigation without the original POST body or referrer. Do not use it to forward submitted form data. Use DNR or network interception for request-level behavior.

A redirect is not a security allowlist. Do not assume every alternative URL or API path to a destination is blocked. The destination URL may appear in the address bar or restored session; the original URL is not guaranteed to remain visible.

Verify

Test direct navigation, a link from a controlled web page, and a new tab separately. For a plugin target, inspect chrome://extensions and confirm its directory name and page file. Re-sign changed EP mappings and relaunch existing instances; editing a Provision EP seed does not update their local copies.