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+This test will verify that the Briar app and mailbox behaviour is as expected when a sender sends invitation to join their private group to the contact who is offline, and who may the MB app installed, or not, and who may export their acceptance or decline via removable media or via mailbox, or answer directly by connecting via internet or BT. 
+
+invite multiple contacts - some of whom are offline some online 
+export the nvitation to removable media 
+invite via internet, but reply via MB
+invite multiple contacts via BT, reply via mailbox, exporting the replies and via internet.
+sender offline, their MB comes online later, then their contact comes online (after the invitation has been uploaded to sender's MB)
+sender doesn't have MB, but the invitee has 
+sender does not have the MB, invitee installs  and pairs it after the invitation has already been created
+
+
+**Scenario 1**
+
+**Sender**
+
+| is online | msg type | has MB | MB online | exports msg | before/after MB upload | receives acks | ack medium |
+| ------ | ------ | ------ | ------ | ------ | ------ | ------ | ------ | 
+| yes | invitation to private group | yes | yes | yes | after | yes | MB | 
+
+
+
+**Recipient1**
+
+| is online | msg type | has MB | MB online | exports ack | before/afterMB upload | 
+| ------ | ------ | ------ | ------ | ------ | ------ |
+|no | invitation to private group | yes | yes | yes | na | 
+
+In this scenario, the sender who sends the invitation is online, and has the MB installed and paired with their Briar app.  The contact whom they want to invite is offline, and also has a MB installed and paired.
+
+- sender sends the invitation to their private group to the contact who is offline
+- invitation is uploaded to their mailbox
+- sender goes offline
+- recipient comes back online
+- they receive the invitation from the sender's mailbox
+- they accept the invitation 
+- their acceptance is uploaded to their MB
+- recipient goes offline
+- sender received reply from the recipient's MB
+
+- this scenario can be repeated with:
+- recipient not going offline after they reply - in which can the reply will be deliered via direct message from contact to contact - as they are both online
+- sender not going offline after their message has been uploaded to their MB.  When their ocntact comes online, they will receive the invitation either via MB or via direct message from the sender's device.  This is transparent to the recipient - the important thing is that the invitation is successfully received. 
+- sender sends the invitation to their private group to a contact who is online, and after that sender goes offline.  That means that the recipient's reply cannot be delivered directly to them, but has to be uploaded to the recipient's mailbox.  Recipient then goes offline.  When sender comes back online they receive the reply via recipient's mailbox.
+
+[Back to Testing](https://code.briarproject.org/briar/briar/-/wikis/Testing)