This extension sees if you are at Amazon.com and redirects you to Amazon's Smile
AmazonSmile is a program offered by Amazon which provides an automatic way for you to support your favorite charitable organization every time you shop, at no cost to you.
The only catch is that the web address is slightly different (you would have to go "smile.amazon.com" instead of "amazon.com"). I often forget this step while shopping online.
This extension will redirect you to the AmazonSmile page whenever you're browsing Amazon, so you'll contribute to your charity while making purchases without sparing an extra thought