Live Routes, Show Direction, Follow, Markers Clustering Show Map on Selection - Explanation?

Unfortunately, I cannot find any detailed explanations of the options in the Traccar documentation at https://www.traccar.org/documentation/
And there are also no videos that explain or show what these options do.

Preferences ->

• Live Routes
• Show Direction
• Follow
• Markers Clustering
• Show Map on Selection

Server -> Permissions ->

• Readonly
• Device Readonly (Duplicating a device with the same unique id is not possible, so Traccar provides a special device readonly user setting to restrict users for modifying devices <- does this mean, if I activate this it would be possible that Traccar create a special device readonly user if I want to share a Device with a User?)

What exactly do these options do when they are on?
I tested the above options under “Preferences”, but I don't see any changes.

Thanks

After searching the forum I think I have understood the meaning behind these options:

• Live Routes
• Follow
• Show Direction

Just not those:

• Markers Clustering
• Difference between “Readonly” and “Device Readonly”

Marker clustering should be pretty self-explanatory. It's either enabled or disabled.

For readonly documentation see this:

https://www.traccar.org/user-management/