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Under Reset Management check all the checkboxes
With the tab TAB-key navigate to the the Reset Button to make it the selected button, so if that pressing the return RETURN-key on the keyboard would trigger the Reset action (see screenshot)
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Open a second browser window with the update tool and upload the firmware, so the confirmation pop-up is shown. Navigate to the OK button with the TAB-key, so the the OK button is selected and pressing Return the RETURN-key would trigger the action (see screenshot)
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