Mozilla Firefox
To clear your cache in Mozilla Firefox, start by clicking on the menu button in the top right corner (). Choose the big Options button:
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In the resulting dialog, go to the Advanced tab, and the Network sub-tab. Here, under Cached Web Content, you'll see a Clear Now button that will quickly clear your cache.
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And that's it already! Simply hit OK at the bottom of your screen and restart your browser, and you'll be good to go!