How are these listed? Firefox has "Search and Form History" separate from browsing history. If the suggestions are shown with a clock icon instead of a site icon, that is search history. You can bulk-flush that category and then set Firefox not to remember any search and form history going forward. I think this article probably is the best place to start:

Control whether Firefox automatically fills in forms

How are these listed? Firefox has "Search and Form History" separate from browsing history. If the suggestions are shown with a clock icon instead of a site icon, that is search history. You can bulk-flush that category and then set Firefox not to remember any search and form history going forward. I think this article probably is the best place to start: Control whether Firefox automatically fills in forms

It took me a few minutes to find what worked in the article, but 'Turn off Auto form fill and prevent Firefox from storing more form entries' seems to be what I needed.

Thank you!

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