I created a new Mastodon account with a display name. Then established that account in /toot/ using the “login” CLI command. I later erased the display name in the web client. But in subsequent usage of the /toot/ app, references to the original display name still persisted. I don’t recall where, but likely when doing a “toot post” from the CLI. It’s a bit surprising that /toot/ would keep a copy of it since it’s unlikely needed for any operations. In principle it should be the server that conveys that sort of profile information.