Trigger action when specific volume is mounted

My use case is the following: I have my email library on an external disk. I want to launch Thunderbird when that particular disk is connected to the USB port.

What I did: Created a new "Automation Trigger" on "NSWorkspaceDidMountNotification", and as an action, launch Thunderbird. On the trigger options, I filled the "Must contain text" field to the name of the volume.

What happens: The trigger activates (and Thunderbird opens) whenever a new volume is detected, independently of the volume name, if it's a disk image or an external disk.

How could I make it so that the trigger only runs when a specific volume name is connected?

See here: Add info from NSWorkspace notifications as context variable - #2 by Dirk

Thanks! It is trickier than I had assumed but this works as expected.