There may be some possible bugs or issues with Google Search Console reporting around some canonical URLs being reported in some URL Inspection reports and for the AMP enhancement report.
Canonical URL issue
The canonical URL can be found under the coverage report, show excluded URLs and then click on "alternate page with proper canonical tag" or the "duplicate without user selected canonical." When you click on those examples and run the URL inspection tool on those URLs, Google is not showing the Google-selected canonical URL.
Yesterday, Glenn Gabe posted on Twitter "Seeing strange things in GSC for canonical urls since the latest changes were announced on 1/11. In Excluded, for canonical reports, Google might say it chose another URL as the canonical, but just provides N/A when inspecting."
Here is that tweet:
Note, I'm seeing this across sites and across canonical reports in Excluded (Alternate page with proper canonical tag, Duplicate, Google chose different canonical than user, and Duplicate, submitted URL not selected as canonical). I believe this started w/the changes on 1/11. https://t.co/0pkP4QZJRj
— Glenn Gabe (@glenngabe) January 25, 2021
Here is a screen shot from my own site:
Confirmed: Daniel Waisberg confirmed this is an issue and is being worked on:
We found a reporting issue with the Google-selected canonical field in the URL Inspection and it should be fixed in the coming days. Thanks!
— Daniel Waisberg (@danielwaisberg) January 27, 2021
Update 2: Seems fixed:
Quick update on the canonical issue I picked up the other day (that Google confirmed). Everything is looking good in GSC now. I'm seeing the return of canonical urls for the various canonical reports in Excluded. Just a heads-up. Thank you @danielwaisberg! pic.twitter.com/XvMn71FpGD
— Glenn Gabe (@glenngabe) January 29, 2021
AMP Enhancement Indexed Dip
A lot of folks also noticed that around the 20th of January there was a dip in the number of pages Google Search Console reported as indexed in the AMP enhancement report. I see this issue too, a dip of about 200 plus pages on my end.
It is not clear if this is a bug, but the number of pages are increasing now over time. Here are those reports:
(2 of 2) Here is a tweet from when the canonical bug was active where I saw a drop in AMP urls & a spike in "Duplicate, Google chose another canonical". I haven't been able to isolate any specific changes this morning based on the AMP reporting changes. https://t.co/0SFKlF5xvK
— Glenn Gabe (@glenngabe) January 23, 2021
I asked for an update and things are improving:
3 sites went back up, 5 sites are still down, they are seeing mobile traffic down with the decline in indexed amp. Interesting indeed. pic.twitter.com/Ja3vkwTBfj
— Ewdison Then (@ewdi) January 25, 2021
But they did not go back to normal for all publishers.
I am not sure if this is a reporting bug or something else.
So these are two issues right now we are seeing amongst many, if not all, site owners in Google Search Console.
