The screenshots below were taken on a PC running Windows 7, but the same steps work in Windows 10 and OS X.

  1. Click on the Menu icon in the top right corner.
  2. Select History.
  3. Select Clear Recent History.
  4. Click Last Hour.
  5. Select Everything. Select a different option if you don’t want to erase every site you’ve visited.
  6. Click Clear Now. You can uncheck other boxes if you don’t want to erase all of your history, because deleting cache and cookies will require you to re-login to sites. Your internet history in Firefox has been erased.

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