Hello @Nick,
I tried to reproduce the issue in my tenant and the behavior is same.
I had created a multi-tenant app registration in tenant A without a logo and a home page URL and tried to access the same app in tenant B which created an enterprise application in tenant B without a logo and a home page URL.
Later, I added the new logo and home page URL in tenant A, where the logo in the tenant B got updated but the homepage URL is still blank in tenant B.
If you didn’t have a homepage URL set when they first consented to your app, it will be created blank in the Enterprise Applications of Clients tenants.
Any later changes you make to the App Registration homepage URL won’t populate it.
To resolve this issue, the tenants who are using this apps should navigate to Enterprise applications > Properties > Enabled for users to sign in to "NO" and save it. Wait for a min and Enabled for users to sign in to "YES" and again save it. Refreshing the page would now populate the new homepage URL.
This is because, the instance is already created and active on the other tenants and making it inactive and active would load the new metadata from the App Registration hosting tenant. Logo updates auto-propagate because they are CDN-based.
Apart from this, if you would like to auto update the URL's the application must be listed as a gallery application where the URL's can be managed and auto synced from the tenant hosting the application.
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