...
Quick actions help users navigate and use Salesforce efficiently by giving them fast access to selected fields. Users can focus on the task at hand and avoid wading through all of the fields contained in an object. Quick Actions can be global or object-specific. For more information about Quick Actions, refer to Salesforce Help - Quick Actions.
...
Deleted Quick Actions may not initially disappear from Pulsar after a catch-up sync, because there is no last modified date.
To make a deleted Quick Action disappear, do the following:
In Salesforce, in Setup, select any Quick Action contained in the same object as the deleted Quick Action.Click Edit.use the Object Manager to select the object containing your deleted Quick Action.
Select Buttons, Links, and Actions in the menu.
Navigate to any Quick Action in the list and click Edit from the menu.
Click Save.
In Pulsar, Refresh Settings and Sync Now.
...