What is the Form Cache button and what does it do if I click it?

Forms will be caching on the caching server that allows to preserve some data of the forms and allows to load the forms quickly. If you observe any issue like the form is not updating or displaying properly after making changes, you may clear the form caches so that the forms are refreshed. Here is the guide to clear the form caches.

https://www.jotform.com/help/229-How-to-Clear-Your-Form-Cache

Hope this information helps!