SPFX solution in site collection app catalog - breaks site for external user

[Ari Bakker]

SPFX solutions deployed to the site collection scoped app catalog (not the tenant app catalog) do not seem to work for external/guest users. In the case of an application customizer a blank page is displayed (effectively breaking the entire site), and in the case of a webpart the the component is not rendered on the page. The same SPFX solution works for non-external users OR if deployed to the tenant scoped app catalog. This affects modern sites but does not seem to affect modern pages on classic sites.

There is a workaround described at https://techcommunity.microsoft.com/t5/SharePoint-Developer/Site-Collection-App-Catalog-External-Use... to grant external users read access to the tenant scoped app catalog, but this grants external users permissions that we would prefer to avoid.

A screenshot of the issue on a modern team site is shown below - note there seems to be an issue returning the HTML for the page as the response is truncated partway through the HTML Head tag:

Has anyone else faced this issue and/or is there a resolution for this issue without having to grant external users access to the tenant app catalog?

[#2]

We raised a support ticket with Microsoft for this issue and it has now been fixed.

[#3]

Hi, we're still having this issue, the external users still cannot load SPfx component. Do you know what MS did as the fixed? 

Thank you much!

[#4]

I don't have specifics on what was done to fix this but I did receive this from MS Support on the 7th of August: "The fix is currently rolling out to all tenants. While some tenants already have the fix deployed, [your tenant] is still not corrected yet. The full roll out can take up to 4 weeks, but we should have it applied to [your tenant] in a few days. Other tenants will have it soon as well (if they are not corrected already)."

[#5]

Appreciate the reply, I'll look into that message. Thanks!