Click the power ⏻ button to toggle uBO for current site whose domain is shown below it.

The More ⮟ and Less ⮝ buttons can be clicked multiple times to successively reveal or hide more functionality.This is the UI dialog that pops up when the uBO button in the toolbar is clicked. The improvement in actual usage was also clear. I clearly noticed a 50% or more reduction in memory usage with uBlock Origin compared to ABP. If you need to turn off blocking or change a configuration just click its button in the toolbar. (Confusingly, there is also a uBlock addon, which is a fork of this.) Just install the addon and you are set! It uses many lists that are maintained online and the blocking is automatic. Searching for a leaner alternative to ABP I switched to uBlock Origin. Using the Task Manager in Chrome I noticed that one of the main culprits was AdBlock Plus which was hogging memory.

I recently switched to an older notebook and my Chrome and Firefox browsers were quite slow on it. 📅 2015-Sep-26 ⬩ ✍️ Ashwin Nanjappa ⬩ 🏷️ extension, firefox ⬩ 📚 Archive

Ublock origin addon