My project is just a WordPress installation deployed to Google App Engine Standard Environment.
According to the list of features, Datastore is not available for PHP, however I can see some Cloud Datastore entries in the Resources card on the project's App Engine dashboard, as you can see here and its' amount grows little by little.
Cloud Datastore dashboard shows me that I have no datastore entries.
I know, I could disable writes to datastore from the Google Cloud Console or even completely deactivate Cloud Datastore API for the project — what I definitely would do if it keeps growing — but I want to understand the causes of these datastore entries and maybe its contents if possible.