Apart from ping that is not supported by Firefox, the rest of the attributes work across the board (even inputmode on Firefox, even when caniuse.com says it doesn't).
From the SEO perspective, these attributes provide additional semantics to the code, which should be something positive for a search engine, but I don't know how much the search engines value them. In the case of cite, the search engines will most likely crawl and index the destination page.
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Apart from
pingthat is not supported by Firefox, the rest of the attributes work across the board (eveninputmodeon Firefox, even when caniuse.com says it doesn't).From the SEO perspective, these attributes provide additional semantics to the code, which should be something positive for a search engine, but I don't know how much the search engines value them. In the case of
cite, the search engines will most likely crawl and index the destination page.