I have noticed that there are times when I accidentally leave timers running over night. At first, I thought it was me being absent minded and forgetting to turn off the timer because you don’t have a browser widget or app that allows it to stay visible on the desktop. I finally figured out the problem. Your start/stop icon is too small. I understand that you have two functions in the same box. You can either click to go to the Time Tracking Log or click the circle to start/stop the timer.
Have you noticed all of the people asking for a way to be able to see if they have timers running? I’ve seen several people asking for that which means other people are also experiencing the fallout from your start/stop button being too small.
When you’re busy and working hard to move from one task to the next, or you’re burning the midnight oil and need to get to bed, you shouldn’t be forced to have a precision click!
You have the click area the wrong way round for UX. The large square with the time should start or stop the timer. Make the little tiny circle with the play icon link to the Time Tracking Log and change the icon to an i for info or a little clock.
If you take up my suggestion, you could really make people happy by making the font of the time red or the background of the cell red.
Lots of people have complained about not noticing they have timers running. Color would make it easier to see if a timer is on that shouldn’t be!