View this Addon on Curse Forge. This is an edit of the Bigger Health Bar addon, credit to it's original creator Slothpala.

• Move the "HUD" folder found inside this directory to "Your World of Warcraft install location_retail_\Interface"
• Restart the game if it is open, a "/reload" is not sufficient.

This will remove the border-separator in between the Health Bar frame and the Mana Bar frame. Without this you will still see the separator when taking damage. For image comparisons of this, see the original addons images in the Curse Forge page, it's linked in the top of this text.

Just like the original Bigger Health Bar addon, this removes the mana bar from your Player Unit Frame, and enlarges your health bar to take up the free space left behind from the mana bar. However, this addon only does this if you're playing a Tank or a DPS. If you're playing a healer, the mana bar will still show. Additionally, this will update your Player Unit Frame to the correct state as soon as you change specialization, you do NOT need to "/reload" for this to work!

I mostly play healers, but sometimes other roles as well. I use a specialization WeakAura in the middle which displays vital information in the middle. I'd argue that Energy/Insanity/Rage etc is more important than mana. I don't need the mana bar in the middle, as I don't need to view it that often, so removing the mana bar from the center WeakAura frees up more vertical space. However, if I don't have the mana bar displayed in the center with a WeakAura, I need something else to display it, hence this addon.