Fixing distortion and red lines when moving items in Diablo III on a MacBook Pro

For season 19 of Diablo III, the wife and I decided that we were not only going
to play the season, but actually set out to complete all of the objectives for
the season.

As we’re pretty much filthy casuals when it comes to Diablo, we did both
accomplish what we set out to do, but not without a major setback that nearly
cost us to season.

Seems recently something changed, either with macOS or Diablo III itself that
cause my wife’s 15” MacBook Pro (last year’s model) to start with some pretty
shitty behavior.

From any screens with items (inventory or chest) the moment she would click on
an item the screen go nuts and made it fairly unusable. The screen would look as

Diablo III distorted with red lines

My first inclination was that she ended up installing something sketchy that
possibly caused this anomaly. Did some malware scans, nothing too out of sorts

Ended up running Apple’s hardware diagnostics, as my next thought was that the
motherboard and/or graphics card was on the fritz. Nothing reported back there.

After some digging, which was a pain in the ass since I wasn’t entirely sure how
to describe what we were seeing, I found that the issue may have been related to
how macOS and the MacBook Pro hardware handles switching between the integrated
graphics card and the dedicated one.

Ended up tweaking a handful of different settings and had a weird mix of results
that never put us consistently out of the woods.

The thing that finally got everything resolved was a combination of configuring
Diablo III to run in low resolution (more on that below) and then simply
changing the display option (in-game) from “Fullscreen” to “Windowed (Fullscreen)”.

To tell Diablo III to run in low resolution mode, you have to track down the
application, right-click (two finger) on it, and click “Get Info”. From there,
you will see an option that’s probably unchecked that says “Open in Low

I made sure to check that option, and closed the info dialog. I also did the
same thing on the application as I wasn’t entirely sure if they both
needed this treatment or not.

The game itself doesn’t actually appear any different visually, so I’m not quite
sure what the low resolution option did, outside of helping us resolve this

Hopefully whatever was broken (either on Apple or Blizzard’s end, or a
combination of the both of them) will be resolved in the future and if not, I
wanted to get this post out there just for my own reference when I forget what
the heck I did to fix it.

Worth nothing that my Dell XPS 15 laptop has a similar setup with an integrated
graphics card and a dedicated one and I haven’t run into any issues like this.
Never thought I’d say this, but “Go Windows”?

Josh Sherman - The Man, The Myth, The Avatar

About Josh

Husband. Father. Pug dad. Musician. Founder of Holiday API, Head of Engineering and Emoji Specialist at Mailshake, and author of the best damn Lorem Ipsum Library for PHP.

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