Test memory leaks using memory profiler available at
chrome-devtools>memory.
Use the profiler in incognito mode.
You
can test it inside code-sandbox but it is strongly suggested that you use
compiled version (see `./dist` folder) because code-sandbox periodically
refreshes the page.
The `heavy-string` is either in
`(concatenated-string)` or in `(string)` section and starts with
`heavy-string-`.
This test shows the impact of long running listeners.
heavy-string len: 100013