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The easiest way of emptying browser cache, no matter which Firefox version you are using, is by pressing the shortcut Ctrl+Shift+Del which opens the window below:
Select in the Time range to clear menu the period that you want to delete from the history, cache etc. The default Everything is the recommended option.
In Details, you can select separately what to delete in case you do not want to delete everyting.
By clicking on Clear Now all selected items are deleted.
Internet Explorer
The same shortcut Ctrl+Shift+Del works also in deleting Internet Explorer history.
Google Chrome
Also Chrome obeys the Ctrl+Shift+Del command. Define the history period that you want to delete in Obliterate the following items from. It is advisable to delete history from the beginning of time, at least on a public computer.
Safari 5
In a Mac Safari browser, history is cleared by selecting Reset Safari in the Safari menu:
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