Steps to reproduce:

1. Use Chrome for testing.
2. Create a new dashboard with a graph widget.
3. Set widget refresh rate to 10 seconds.
4. Save the dashboard.
5. Open Chrome's Development tools and navigate to "Memory" tab.
6. Take Heap snapshot (button).
7. Wait more than 10 seconds (until the next refresh cycle is done).
8. Take Heap snapshot again (button).
9. Select "Objects allocated between Snapshot 1 and Snapshot 2".
10. Write "DOMTimer" in the "Class filter".
11. Repeat steps starting from 6.

Result:

Number of DOMTimer instances is constantly growing after every refresh.

Expected:

Number of DOMTimer instances should not be constantly growing.