We currently have custom implementation for scrollbars.
Reasons to remove:
* Less code to maintain
* Hopefully fewer errors like: https://jira.ixsystems.com/browse/NAS-109922
* Slightly better page performance
* We will keep default OS scrollbar behaviour and configurability. (i.e. scrollbars are hidden by default on macOS when touchpad is used).
Reasons to keep:
* Same look an feel across different platforms