By Default, Focus will block all of the sites included in its Blacklist. However, if you want, it is possible to turn Focus’ Blacklist into a Whitelist (of sorts), making the list work in the opposite manner. By this method, Focus will block ALL websites and allow only those websites that you specify.
This is done in two steps:
Block All Websites
Add Allowed Sites
Delete all entries in the Blocklist and replace them with a single asterisk,’*’. This single wildcard instructs Focus to block all websites.
After the wildcard, include each website that you would still like to access while the Focus session is active, making sure to precede each website with a ‘+’.
Allowed Site Exceptions
With Allowed Site Exceptions you may block an entire website but allow access to only a few specific pages within that website’s domain. For further instructions on implementing this feature see Advanced URL Blocking.