Back in the day I used an addon called Button Forge, it's unfortunately no longer being maintained.

On the healer I made a button forge action bar and place e.g. Tranquility on there. Then I would create a weak aura on the tank that would track the CD status of the healers Tranq, with a repeater region (whenever I needed tranq I would then activate it from the tank). Has always been my preference over Video FX.

Is there another method boxers use lately?

Edit: I don't want to use Bartender nor Dominos for various reasons.