I am using the JavaScript SDK but encountered error "b is undefined" even when I am using the sample code. What is wrong?





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The "b is undefined" error will occur when you try to load both the old JavaScript SDK (which is sometimes referred as the JavaScript Client Library) and the new JavaScript SDK (which can be downloaded from

  • You can find references to the old JavaScript SDK by searching for the string "FeatureLoader.js.php".
  • The new JavaScript SDK is loaded as "all.js"



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