add example of using setTimout to close the popup

Author: zendive

README.md

@@ -12,6 +12,7 @@ To expedite issues discovery, here are some examples from experience:
 - A bundled dependency library that utilizes the eval function, thereby preventing the removal of `unsafe-eval` from the Content Security Policy (CSP) header. It can be arguably intentional, but also may reveal a configuration issue when the package was bundled with webpack config's [devtool: 'eval'](https://webpack.js.org/configuration/devtool/) in production mode.
 - A substantial number of hidden video elements in the DOM that were consuming resources, unexpectedly limited to 100 medias per domain.
 - An unattended interval that was unintentionally left running and contributed to a slowly growing memory.
+- A hard to find/replicate (with touchpad) bug, - when popup closes on click on one of its popup buttons without acting on those buttons, if time between mousedown and mouseup is larger than 100ms. The intent of underlying code was to detect "click outside" case to close the popup, but this implementation caused frustration to mouse device users with heavy/tired/slow finger.
 
 To explore the internals of a complex systems.