Mobile URLs Won’t Need to be Included in Sitemaps for Mobile-first Indexing
It won’t be necessary to include mobile pages in sitemaps for Mobile-first indexing. You should continue to include on your canonical desktop pages. Google’s goal is to keep everything as similar as possible while indexing content on mobile pages.
Sitemap Errors don’t Impact Rankings but can Slow Down Indexing
Sitemaps help Google improve crawling and indexing of sites. If a sitemap can’t be properly processed, Google may take longer to index pages as have to rely on normal crawling and indexing to find those pages.
Add Images to Sitemap to Provide Google With More Information
Images can be added for each page of your site within your sitemap along with captions and alt-tags using special sitemap extensions.
Sitemap Index Counts Report the Exact Submitted URLs
Sitemap Index counts report the exact URL you sumbit including trailing slashes. If Google chooses to index a different copy of the same page, the submitted URL wouldn’t be reported as indexed.
Hreflang Data in Sitemaps May be Shown as ‘No Return’ Error Until the URLs are Recrawled
Until pages have been recrawled, you might see hreflang ‘no return hreflang’ errors in search console for hreflang data added to a Sitemap.
Identical Last Modified Dates in Sitemaps for all Pages will be ignored
If all the last modified dates in Sitemaps are identical, Google will assume they are incorrect.
Google Automatically Chooses a Preferred Domain Based on Multiple Signals
Google uses many factors to determine the canonical domain including redirects, canonicals, internal links, sitemaps and backlinks, so choosing a preferred domain in Search Console is not critical.
Sitemaps Require Absolute URLs and Recommends for Internal Links
Relative URLs are fine for internal linking, but Google requires absolute URLs for Sitemaps. Google now recommends using absolute URLs for internal linking to avoid any uncertainty about the preferred protocol.
RSS with Pubsubhubbub to get URLs Indexed
You can use an RSS feed with Pubsubhubbub to ping Google with new URLs as an alternative to Sitemaps.