what does the blue dot beside an announcement mean?
The blue dots to the left of the Announcement is an "not read" indicator; meaning that you have not clicked on the announcement to view it (if you read an announcement as a instructor that is delayed, the blue dot will remain until it is published/posted and you access it again).
Normally in Canvas a blue dot appears next to something that is unread. So that you can easily tell what announcements you haven't seen/read yet.
Although I know Sky and Brian are right, this feature has been buggy, at least for me and a few instructors I know. So if the dot is still appearing next to discussions or announcements that you've read, it may be a glitch.
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