When you clear your cache you will always load the latest version of a webpage. So make sure you download the latest data from any website.
To clear cache in your Firefox browser follow the next steps.
 
1. Clear browser data (cache) in Mozilla Firefox with the keyboard shortcut.
  • Press the keys [Ctrl], [Shift] and [Del]
  • A new Window opens calles "Clear recent history"
  • Select your time frame, Last Hour .... Everything
  • Select only the check mark in front of Cache. De-select all other check marks
  • Confirm your selection by clicking the "OK" button
2. Delete the browser cache in Mozilla Firefox through the menu.
 
  • Click the menu button (3 stripes) and select Options.
  • Select the Privacy & Security panel on the left (lock symbol)
  • Scroll to the Cookies and Site Data section
  • Click the button "Clear Data…"
  • Select only the Check mark in front of Cookies and Site Data.
  • De-select the other check mark in front of Cookies and Site Data
  • Click on the Clear button
Close the about:preferences page. Any changes you've made will automatically be saved.

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