A problem in js file: knockout-3.2.0.js

I run my code with Cesium’s Sandcastle,report the error below:

mutating the [[Prototype]] of an object will cause your code to run very slowly; instead create the object with the correct initial [[Prototype]] value using Object.create knockout-3.2.0.js:10:197.

this js file path is ‘cesium16/Source/ThirdParty/knockout-3.2.0.js’, cesium version is 1.16.

any one can help me?thanks.