Add prototype to descriptions

snippets/isPlainObject.md

@@ -5,7 +5,7 @@ tags: type,object,intermediate
 
 Checks if the provided value is an object created by the Object constructor.
 
-- Check if the provided value is truthy, use `typeof` to check if it is an object and `Object.constructor` to make sure the constructor is equal to `Object`.
+- Check if the provided value is truthy, use `typeof` to check if it is an object and `Object.prototype.constructor` to make sure the constructor is equal to `Object`.
 
 ```js
 const isPlainObject = val => !!val && typeof val === 'object' && val.constructor === Object;