SharePoint Framework App-extension error


I'm facing an issue following the dev article for creating an App-extension. Following this article, the step where you're asked to gulp-serve and append an existing list with the following code.


?loadSPFX=true&debugManifestsFile=https://localhost:4321/temp/manifests.js&customActions={"d03ae0c2-bbbf-4cf5-9ff7-0986904553da":{"location":"ClientSideExtension.ApplicationCustomizer","properties":{"testMessage":"Hello as property!"}}}


I have replaced this code with my own ID an tenant name, resulting in the following URL.{"7c36083f-4b95-43a3-ad8c-d8ed500043a2":{"location":"ClientSideExtension.ApplicationCustomizer","properties":{"testMessage":"Hello as property!"}}}

2017-06-09 10_55_44-HelloWorldApplicationCustomizer.manifest.json - app-extension - Visual Studio Co.png



Browsing the URL results the console error below. Does anyone have an idea what might cause this problem?

2017-06-09 10_58_32-Developer Site - test - All Items.png

4 Replies
Did you get the modal popup window to load debug scripts?

Hi Luis,


Yes I got the pup-up and chose "Load debug Scripts".


It might be the case that my developer tenant is not yet having the updates for the app-extensions.

One of my co-workers did have a message in the message center which indicated that the release was available on the tenant. I dont have this message yet.




best response confirmed by Rémy Bosman (Contributor)

according to yesterdays monthly PnP Webcast it should be active on all dev tenants now. Can you check it? :)

I just checked, and indeed it works now :)