LimitSurf

This extension makes you more productive by letting you set custom time limits for websites. - Completely block websites by setting 0 as the time limit - Set time limits for websites - Set time limits for specific subdomains like youtube.com/shorts We have no access to any of your data. It is not saved or processed by us. All data about your limits is saved only to your own google account so that your limits sync across devices. We cannot see which websites you block or how long you spend on them.

Screenshots from Chrome Web Store