Object doesn't support property or method 'contains' in ie11
this line breaks in IE11: https://github.com/casesandberg/react-color/blob/bc9a0e1dc5d11b06c511a8e02a95bd85c7129f4b/src/components/common/Saturation.js#L23

because 
![image (17)](https://user-images.githubusercontent.com/1305378/114675334-66819680-9d08-11eb-8f9c-f756abd262c1.png)

so it would be nice to do one of the following:

1. warn users that this lib is not compatible with ie 11
2. either include a polyfill or change the method used to check for containment to something like this https://github.com/ljharb/document.contains/blob/main/implementation.js