We have come up with the below content for both MS support and other public forums tickets.
My provided hosted APP Part not listed in SharePoint 2019 modern pages, but I can see same provide hosted APP Part
working in SharePoint online modern page.
I have installed provider hosted APP in my SharePoint 2019 site collection. I have created a modern page and when
I click on the add webpart ( + symbol) my APP Part not listed there.
And I created a wiki page (classic page) in the same site collection and when I click on Add APP Part in the ribbon
and I see my APP Part listed and I can add my APP Part in the page.
Though, I can add my APP Part in SharePoint online modern Pages.
I have activated “SharePoint Server Publishing Infrastructure” at site collection feature and have activated “SharePoint
Server Publishing” at site features as well in SharePoint 2019 on-prem.
Why my APP Part not listed in SharePoint 2019 modern pages and listed in SharePoint online modern pages? I have
a latest patches DEC 2020 CU installed in my SharePoint 2019 on-prem environment.
SharePoint 2019 Modern Pages
|
APP Part not listed
|
SharePoint 2019 classic site pages
|
APP Part listed
|
SharePoint online Modern Pages
|
APP Part listed.
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