GSC Registers Impressions Based on Results Served, Not What is Displayed in the Viewport
Search Console registers an impression based on the search results shown on the page regardless of whether or not it is visible in the searcher’s viewport or not.
Use Testing Tools to Identify if Your Site Has Hacked Content That is Being Cloaked
If you suspect you have hacked content that is currently being cloaked from search engines being able to see, John recommends using testing tools including the inspect URL tool in GSC to identify if Google is finding this content.
Only One Version of Same Content On Different Country Sites will be Indexed & Appear in GSC Performance Reports
If you have the same content on multiple language variation sites, Google will pick one to index but will use hreflang attributes to swap out versions of the page based on a user’s location. However, only the page that has been chosen to be indexed, and used as the canonical, will be displayed in the GSC performance report.
Google Has a Separate User Agent For Crawling Sitemaps & For GSC Verification
Google has a separate user agent that fetches the sitemap file, as well as one to crawl for GSC verification. John recommends making sure you are not blocking these.
The New Fresh Data Seen in GSC will Differ Slightly Until Things Have Settled Down
The new fresher data now available in Search Console is calculated in a slightly different way, in order to get the data into Search Console as quickly as possible. Therefore, John noted there may be slightly different counts from when it is fresh compared to when it has settled down.
When Displaying Rankings For Pages in GSC it Will Count the Topmost Position in that Search Results Page
If a page is shown more than once in search results, for example as a featured snippet and in the fourth position, then GSC will display the topmost position for it. In the example case, it will display the page as position one. However, this will depend on whether you are looking from a URL level or a query level.
When Displaying Page Positions in GSC it will Start at Position One
If your page is being shown as a featured snippet in position zero, it will appear as position one in Google Search Console, as the numbering they use starts at one.
If Content is Loaded After an Interstitial is Shown Google Will Not Be Able to Index the Page
Googlebot does not interact interstitials, e.g. GDPR notice. Instead, it will try to crawl and render the page as it comes. If you are using one on top of the HTML content then Google will still be able to view the rest of the page, however if the content is only loaded after the interstitial is accepted, Google will only be able to see the interstitial and will try to index this, rather than the actual content.
Use Redirects & Canonical Tags to Stop Data From Other Site on Same IP Being Included in GSC
If there are internal links between two sites on the same IP address, data for both sites can sometimes appear in the same GSC account. If you don’t want Google crawling the other site then add redirects or canonical tags pointing to the main site.