How to view task work history?
From Planfix
In task cards, there is a "Log" tab. This tab shows the entire history of work on a task, from creation to completion. In the log, you can see who was linked to the task, who added comments, who added files, who changed the task status, and more. You can also see when these events took place.
You likely won't need the log in your day-to-day work, but if any issues arise, you can use it to figure out who did what, and when.