A React SPA with dynamic Helmet → the meta tags are added after the page loads and JavaScript runs.
The initial HTML does not contain the meta tags → any crawlers that do not execute JavaScript will not see them.
React Snap tries to pre-render, but it does not solve the problem for dynamic meta if it depends on props, state, or API data after mount.
Use a library like vite-plugin-ssg with pre-defined meta for each route.
The meta tags will be added to the final HTML for each page before React loads → SEO-ready even for crawlers that do not execute JavaScript.
Limitation: this solution requires each page to have a fixed URL and pre-known meta at build time, meaning the meta cannot be dynamic after mount.