The phrase "extra click" means having to perform an additional action or step, usually online, in order to complete a task or reach a desired outcome. Full definition
Seeing the giving actions of your friends and acquaintances could motivate others to give too, especially when it doesn't require more than a couple extra clicks. (treehugger.com)
In reality, it only takes a few extra clicks... and if you're using an optimized credit card, you'll rack up those points in no time! (upgradedpoints.com)