Maybe this is related to that thumbnail "experiment" they were running a few months ago where users were randomly selected to start seeing auto-generated thumbnails rather than custom ones?
You can add location information to your Tweets, such as your city or precise location, from the web and via third-party applications. You always have the option to delete your Tweet location history. Learn more
Maybe this is related to that thumbnail "experiment" they were running a few months ago where users were randomly selected to start seeing auto-generated thumbnails rather than custom ones?