Add canonical URL to paginated pages in Webflow

canonical-if-pagination-comments.js

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// This code should be placed in the before body custom code
// section on pages that have paginated CMS lists

// get the canonical tag already set in site settings or manually added
const canonical = document.querySelector('link[rel="canonical"]');
// get the params on the URL
const urlParams = new URLSearchParams(window.location.search);
// specifically, get the pagination params Webflow uses
const paginationParam = Array.from(urlParams.entries()).find(([key]) =>
  /^[a-z0-9]{8}_page$/.test(key)
);

// if those parameters exist
if (paginationParam) {
  // update the canonical URL to include the pagination params
  canonical.href = `${canonical.href}?${paginationParam.join("=")}`;
}