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Open Chrome
Right click in the browser window and choose 'Inspect'
Once the inspector is loaded, identify the refresh button on the browser address bar
Right-click the refresh button and choose 'Empty cache and hard reload'
OR
Navigate to the Chrome menu button and Select ‘More Tools>Clear Browsing Data…’
Select the following, and choose ‘Clear data’
Firefox
Click the menu button
and choose Preferences.
Select the Privacy & Security panel.
In the Cookies and Site Data section, click Clear Data….
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