I’ve noticed more and more elec connections have a little tab or plastic something to keep the connection in place, supposedly  makes connection better?

I broke a plastic tab today using a nail trying to get connection apart.

What do you use?

I used an incantation passed down from generation to generation.  It gets better over time and dates back to the civil war, but I may not be using the right one.  Using a civil war Sergeants Incantation about enlisted men explains why my electrical connections get stuck too.  

 

In all seriousness, I use a combination of small to large screwdrivers, lots of rocking back and forth, cleaning the connection, oiling it with penetrating oil sometimes, and prying just short of breaking or bending plastic.  When you do get it apart, use some dielectric grease and you likely won't have problems in the future. 

Would this work on Mopar stuff?

 

https://www.amazon.com/OTC-4460-Electrical-Connector-Separator/dp/B00BVL7LUY

 

Those tabs get brittle with age and will brake sometimes with the slightest of pressure.  When reconnecting along with dielectric grease I'll use a zip-tie to keep them together.  Don't know about the tool, I have my on special thingamajig that I use along with four letter word instructions.   

Hmmm... If the connector is dry already I found compressed air will help getting them apart. Blasting air in the joint of the plug sometimes will move dirt and dust out making them separate easier. Like others said PB blaster, etc to help lube it up if the connector is clean. Small screwdrivers... Some time combinations of all the above. Where the PB blaster and compressed air will drive the lubricant into the plug making it slide easier. 

I've found tapping on them with a screwdriver handle helps knock any dirt or debris loose from them. I try not to use lube on them unless a last resort.