I use 4SEO. Do I need sh404SEF additionally?
They are unrelated.
- sh404SEF is an older extension focused on fixing Joomla SEF URL system. It also has some SEO features such as meta data editing, limited structured data generation, OpenGraph generation, redirections management and few more things.
- 4SEO is a modern (released last year) all-ine-one extension. Instead it provides the full range of SEO features you can need in 2022: full structured data, sitemaps, OpenGraph, Meta data management, broken links detection, Core Web Vitals real measurement, content replacement and more.
4SEO does NOT deal with SEF URLs at all, so that it can work with Joomla SEF URLs, sh404SEF SEF URLs or any other SEF extension URLs.
If you are not familiar with SEO, I would say you don't need to bother about SEF URLs, that's a rather advanced topic which may need more involvement on your side.
I'm afraid I can't direct you to any SEO professional that can work on your Joomla site right now. Maybe a place to look would be the Joomla service provider directory?
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