(See also http://buildfocus.userecho.com/topic/1102942-add-a-i-failed-to-focus-button-to-handle-distractions-outside-of-chrome/)

I suppose I can work-around for now by creating an "I failed" button by bookmarking a blacklisted site :-)

An interesting idea: the "I failed" button could be used to help the app learn better rules for auto-failing. For example, if you click "I failed" after visting a site which is not currently blacklisted, then buildfocus could offer to blacklist it for you. Or later, if you do add currently-focused window support, buildfocus could notice that you clicked "I failed" after switching to Thunderbird and say "do you want me to blacklist Thunderbird while you're trying to focus"?