See the attachment for instructions to clear Firefox browser cache.
Firefox Clear Browser Cache
Firefox Instructions Updated for new versions of Firefox
November 2018 revised
Locate the menu options icon and click this button. Click OPTIONS from menu.
Click the “Privacy & Security” button as shown below.
Scroll down to the section “Cookies and Site Data” as shown below. Click the “Clear Data” button.
Be sure that “Cookies and Site Data” is checked as well as “Cached Web Content”
Click “Clear” button. See next page.
Click the “Clear Now” button to clear this data.