Comment by ndiddy

Edge has a feature where it will periodically pull the bookmarks and browsing history from any other browsers you have installed, so they'll then get sent to Microsoft and associated with your Microsoft account. This was initially enabled by default without the user's consent, although I believe now you may have to opt into it if you do a fresh Windows install. I only realized this was a thing because one time my work PC rebooted to install an update, then Edge came up instead of Firefox, but with all my Firefox tabs. I guess this was part of some effort to try to trick old people who wouldn't notice the difference into switching to Edge. Here's a news article about someone else running into this when it started happening: https://www.theverge.com/24054329/microsoft-edge-automatic-c...