The TaE maintainer, Russ, has been very positive about this widget. At the time of writing, he is working to include it in the main TaE repo/distribution.
In the meantime, you can get this in two ways:
The 'master' branch, which is a ready-for-install replacement of TaE 0.11.
The 'export' branch, which has adds/replaces files in TaE.
README.md setup.py timingandestimationplugin/api.py timingandestimationplugin/htdocs/StopwatchControls.js timingandestimationplugin/htdocs/StopwatchDisplay.js timingandestimationplugin/htdocs/Toggler.js timingandestimationplugin/htdocs/stopwatch.js timingandestimationplugin/stopwatch.py