So, keep in mind that the auto-fill data of your Safari browser, such as saved usernames or passwords, will also be deleted. This problem can be resolved by resetting the browser, which makes it run faster.To reset Safari on a Mac, you will need to take a few steps to remove all its temporary components and installed plugins.
Usually, that happens because of too many temporary and junk files that the browser has created. Over time, however, the app may start running slower. Safari is the most popular web browser for Macs.