As long as the scrollbars of your WordPress site are disabled, only the content inside the sections will be visible. That's the reason why you can't scroll to the footer when using fullpage.js in WordPress.
So the solution is as simple as moving the footer inside a section. But do not worry, you do not have to do it manually Our WordPress plugins for Elementor and Gutenberg already offer an option to do it: the "Show Theme Footer" option.
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