Hello, A few weeks ago I logged into an online account (Strava) and noticed an unfamiliar email in the suggestion box that appears below the email entry box when an email is entered. I ignored it at the time but recently logged into Facebook and saw the same email in the list of remembered login emails. I found the person who owns the unfamiliar email address through my university’s internal lookup service; I have never met the person and I never let anyone access my computer without my knowledge and consent. I am concerned that this person could somehow be accessing my Firefox account and/or other online accounts and the rest of the data on my machine. Is this concern valid given what I’ve noticed? Under what circumstances will Firefox remember an email address so it can be suggested at a later login (ie, does someone have to log in to the particular device being used, or is there another circumstance in which Firefox could remember a login email?) If my concern is valid, what should I do? Note that I have never had Sync enabled, to my knowledge. System information: OS: Ubuntu 16.04 Machine: 2017 Lenovo IdeaPad 320 64-bit Firefox version: Firefox Quantum 67.0.4. I have never had Sync enabled, to my knowledge. My background: I consider myself basically computer-literate but have very limited knowledge of internet security, Firefox’s inner workings, and how web browsers work in general. Thank you!