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in the notification phase, when the aggregated number of group members to mention is above 5 a certain threshold, we are showing a warning modal (see wireframe), the text message in the modal includes the user count from the largest group in the collection. This is a compromise solution, due to performance constraints - fetching the accurate count, including membership overlaps, from the server would introduce a delay in sending the notificationexplained further below.
For example, if we mention
@developersand@board, where@developershas 10 users within the channel while@boardonly has 2 members in the channel, the warning modal will explain that you are about to notify@developerswith 10 members in the channel. If two groups have repeating users the total count shown by the dialog would have to be the intersection union of members for each group within the channel. This would cause a significant performance regression and cannot be done for the MVP.
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