MS Graph APIs - open extensions API should support both primary mailbox as well as shared mailbox

Hi,

The following MS Graph APIs are working only for primary mailbox and not working for shared mailbox. Hence there is no way to set/get custom properties for emails in the shared mailbox. This is required for classifying emails as processed based on these custom properties.

" POST https://graph.microsoft.com/v1.0/users/<sharedmailbox ID>/extensions
Content-type: application/json{
    "@odata.type":"microsoft.graph.openTypeExtension",
    "extensionName":"<extensionName>",
    "extensionProperty": <extensionProperty>
}

GET `https://graph.microsoft.com/v1.0/users/<sharedmailbox ID>/messages/${itemId}/extensions/Microsoft.OutlookServices.OpenTypeExtension.iM.docId`;

PATCH `https://graph.microsoft.com/v1.0/users/<sharedmailbox ID>/messages/${itemId}/extensions/Microsoft.OutlookServices.OpenTypeExtension.iM.docId`;
{
    "@odata.type":"microsoft.graph.openTypeExtension",
    "extensionName":"<extensionName>",
    "extensionProperty": <extensionProperty>
},

DELETE `https://graph.microsoft.com/v1.0/users/<sharedmailbox ID>/messages/${itemId}/extensions/Microsoft.OutlookServices.OpenTypeExtension.iM.docId`;
{
"@odata.type":"microsoft.graph.openTypeExtension",
"extensionName":"<extensionName>",
}"

So open extensions API (GET/POST/PATCH/DELETE) should support both primary mailbox and shared mailbox.

Thanks

Maju

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