Is your feature request related to a problem? Please describe.
No, it isn't but we do have IDs for everything else (and unless I am blind), I cannot find the option to show NPC IDs.

Describe the solution you'd like
Add the option to get the NPC ID.

Describe alternatives you've considered
idTip AddOn does this but I would rather not have two AddOns for tooltips.

Good idea! Will be included in the next release. 👍