Could you add a new feature?

[ayuanx]

When choosing a directory from the drop-down list on the left, it would be
quite convenient if the drop-down list on the right could automatically select
the corresponding directory which was paired with the directory on the left in
previous synchronization.

A very simple feature but essentially useful.

[Zenju]

This is only feasible if selection on the right would mean changing a right
side only. But then we'd have an asymmetry in design with no visual clue on
how it works. Unless there is some other design which solves this problem more
elegantly, changing both sides at the same time is probably best managed via
configurations.

[Zenju]

Additional complication: Folder drop-down on one side can be used to select
aliases/insert macros.