In Thunderbird, I have "Show Tasks in Calendar" enabled. I can now see tasks on my calendar. To mark a task as completed from the calendar view, I have to go through the following procedure:
Double click the event
In the popup, click "Edit"
In the edit dialog, change status from "Not specified" to "Completed on"
Click "Save and Close"
This is an insane number of steps to mark a task as complete, a major impediment for anyone trying to be productive rather than fiddling with the interfaces.
When a task is selected in the calendar view and you open the "Events and Tasks" menu, the "Mark Completed" option is disabled. WHY?
Why is there no "Mark completed" item in the right-click menu? What about a keyboard shortcut?
Make the checkbox icon at the left of the task clickable to mark it as complete/incomplete with a single click. Tasks in Google Calendar operate this way (see the three green tasks stacked on May 20 below, the white square is clickable to toggle completion).
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