You are wondering whether it is possible to recover feed updates or comments from your Jam site that were accidentally deleted.
SAP Jam Collaboration
Only documents (Jam content) go to the trash, not comments (which feed items are) and cannot be un-deleted. In addition, when you delete a document and restore it, the comments for that also do not get reinstated.
2083001 - Feeds and Who Can See Them - SAP Jam
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