I started using LeechBlock several years ago when I still used google chrome, I was having issues with distractions during working hours on websites like youtube and instagram. I was pleasantly surprised with how easy it was to setup, while also considering all the possible ways someone might want to regulate there time and usage of certain webpages. I used the plugin for years on google chrome and when I switched to firefox has happy to see that the plugin looks and acts identical on firefox as it does on chrome.