I just realized that many add-ins cannot be loaded in Excel Online (Chrome):
Does anyone know what's happening?
This is a known issue reported through StackOverflow and other channels. We're investigating this as a high priority issue. We'll let you know when the issue is resolved.
来源：https://stackoverflow.com/questions/46670563/we-couldnt-connect-to-the-catalog-server-for-this-add-n