Phil Nebre Thanks for posting your question in Microsoft Q&A. Based on our discussion, you were trying to add users with TargetingFilter for a key via Feature Manager and hit the limit.
Currently, we have 10 KB limit for a single key-value item including all metadata and unfortunately, this cannot be increased. Alternatively, you can use groups instead of users to avoid this limit. We will add a note to our documentation (#109613) to specifically call out this limitation and appreciate your feedback.
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