In a dual-display Lister, a folder tab on one side of the Lister can be linked with a tab on the other side. When two tabs are linked, selecting one in the Lister to make it active automatically activates the linked tab too. Linked tabs are displayed in different colors from unlinked tabs, and you can configure these colors from the Directory Opus Colors page in preferences.
You can hold various qualifier keys down to modify the linked state of a tab when you click it:
You can also place linked tabs into Navigation Lock mode, using the Navigation Lock option in the context menu. When linked tabs are in this mode the destination tab will always follow the source tab whenever the folder changes, in a similar manner to Navigation Lock.
Navigation Lock is not to be confused with Locked Tabs.