Those who have a Canon printer ( as I have two ) please read. There are ways to prevent your network credentials being retained when you older printers are resold or tossed out. A vendor model list can be downloaded at this link.
The list of Canon printers impacted by this issue is too extensive to include, comprising 196 inkjet, business inkjet, and large-format inject printer models from the E, G, GX, iB, iP, MB, MG, MX, PRO, TR, TS, and XK series.
https://www.bleepingcomputer.com/news/security/canon-warns-of-wi-fi-security-risks-when-discarding-inkjet-printers/