Clear cache (only relevant for template, CSS, JS or PHP function changes

Certain files of the wisy installation are minified and cached to speed up page load times. Therefore, when making changes to the source code (not the content!), the cache must be learned to regenerate these files.

This option has nothing to do with your browser cache and does not clear it. How to clear the browser cache you can read e.g. here: https://browsercache-leeren.de/