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When the app gets added to a channel the first time, an inital process starts, that will crawl over all already existing messages in the channel. The messages are called from the MS Graph API starting with the oldest message. This process can take a while, depeding on the amount of messages and links our app has to extract. The link URLs are saved in our database during the process. The client will then call our service, which responds with the links saved in the database.
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