I'm developing an Outlook add-in, in which I grab the mailbox item id and send it to an API. The API uses the Microsoft Graph SDK to fetch the message item by the given id. This scenario worked fine so far, but now I'm struggling with a strange format mismatch between the id I get from Office.js and the id from Graph.
Office.context.mailbox.item.itemId returns ...MlPrBwD/Cohwu0F...
Graph returns ...MlPrBwD-Cohwu0F
So Office.js returns the id containing /C where Graph returns -C in it.
Any ideas?