Hide neutral units but show when selected, on mouseover or part of a quest; see the Options section for options.
This is a modification of the one that is included with Plater. This modified version will still show neutral NPCs that are part of a quest, has a raid marker set on them, are rare/elite (if those options are set to do so) or has a custom color set within Plater 'Npc Colors and Names'.
If you are wanting to always show a neutral NPC, such as the Algon's in Nazjatar, just add their NPC ID and/or Name into the table under Options.
Also, if you would like to always show a neutral NPC that has a certain buff/debuff, just add the buff/debuff aura ID and/or Name into the table under Options.