Last Activity timestamp is more recent than Last Viewed timestamp

The last activity timestamp is more recent than the last viewed timestamp for the same user on the same board. I would think the last viewed timestamp should always be the same or later than the last activity, as viewing is required to complete an activity. Can someone please explain what triggers each timestamp?

As of 1:41pm, the last Activity was 30 minutes ago. However, as of 1:40pm, the Last Viewed timestamp was 39 minutes ago. Same user, same board.

Its possible if the user created automations or integrations with an app. Those can execute in the background, and don’t require the user to view anything. However, if they execute, they appear as activity of the user because they run as the user (particularly apps and integrations).