Select All Aliases of Region   ⌥⇧A

Selects all aliases of the currently selected region.

Create MIDI aliases in the Logic Pro Tracks area — Apple Support

You can create an alias for a MIDI region or a folder. An alias is a reference to a region, and looks similar to a normal region in the Tracks area. If you alter the original region, all aliases of the region are similarly altered.

Select regions in the Logic Pro Tracks area — Apple Support

To perform some edits on regions, you must first select the regions. You can select one or multiple regions, select regions on different tracks, and quickly select muted regions, overlapped regions, or regions meeting other criteria. Selected regions appear brighter in the Tracks area than unselected regions.

NB When making aliases it is important to make sure that Preferences/General/Editing:’Select regions on track selection’ is not checked. That way you can select a region, select a track, move the playhead, and create the alias in that spot. It is probably a good idea to create a keyboard shortcut for the command ‘Toggle Select Regions on Track Selection’.

  Select Previous Region/Cell/Event or Move Marquee End (or Marquee Point) to Previous Transient    ←

The classic left arrow. Select the previous “thing”. This is one of the highly overloaded key command — five more commands that take higher priority depending on context.

I wonder why they simply didn’t define it as multiple commands — the Marquee descriptions can be confusing.

Select regions in the Logic Pro Tracks area — Apple Support

To perform some edits on regions, you must first select the regions. You can select one or multiple regions, select regions on different tracks, and quickly select muted regions, overlapped regions, or regions meeting other criteria. Selected regions appear brighter in the Tracks area than unselected regions.

Select parts of regions in the Logic Pro Tracks area — Apple Support

Marquee tool: Use to select and edit region parts by dragging across them. The Marquee tool looks like a crosshair.

  New Tracks for Selected Regions

Creates new tracks for the selected regions. The clarification in the documentation is that a new track will be created for each _source_ track, not a new track for each region. All the regions from ‘Track A’ get moved to a new track, ‘Track A New’.

Create tracks using existing channel strips in Logic Pro — Apple Support

In Logic Pro, select the regions, then choose Track > Other > New Track For Selected Regions.

The selected regions are moved from the source track to the new track, which uses the same channel strip as the source track. In other words, only one channel strip is used for all tracks.

If you use this command with regions selected across several tracks, a new track is created for each source track. For example, if you select regions on three source tracks, three new tracks will be created for the regions.

  Select Previous Region/Cell on Focused Track    ←

Selects the previous region. The selection is _circular_. If the first region on the track is selected the command will wraparound and select the last region on the track. OK by me.

The specific command is not documented any more than its entry in the list of Global Commands.

Select regions in the Logic Pro Tracks area — Apple Support

To perform some edits on regions, you must first select the regions. You can select one or multiple regions, select regions on different tracks, and quickly select muted regions, overlapped regions, or regions meeting other criteria. Selected regions appear brighter in the Tracks area than unselected regions.

  Select All Orphan Aliases

Selects all orphaned aliases (MIDI alias regions where the original has been removed).

It takes a lot of work (many dialog responses) to orphan an alias. Not sure how you could get very many, but some workflows are different.

Create MIDI aliases in the Logic Pro Tracks area — Apple Support

In Logic Pro, choose Functions > Region Alias > Select Orphan Aliases (or use the corresponding key command).