I’m running a MacBook Air M2. It’s slotted into my multi-monitor desktop with a CalDigit Thunderbolt hub and an Elecable dual HDMI adapter using DisplayLink technology. I have to use DisplayLink because Mac Silicon (M1 & M2) only support one external monitor natively in the MacBook Air. You need extra hardware to support more.
Everything seemed to work perfectly until I recently found I was unable to watch ANY videos that use copy protection (like Netflix, Prime Video, Udemy) while connected to my monitors. I found four workarounds.
UPDATE (Jan 16 2023) WORKAROUND ZERO: Turn off hardware acceleration in the settings of a Chromium-based browser like Edge or Chrome.
I have tried this with Chrome, Edge, and Firefox on Mac. It worked on Chrome and Edge (both Chromium-based), but not Firefox.
What about Safari? Safari does not have a control for it I could find in its settings and it may not be possible (or you’ll have to hunt harder than I did for how to do it). So if Safari is your primary browser, download Chrome or Edge and use them (with hardware acceleration turned off) to watch protected content while connected to a DisplayLink adapter.
WORKAROUND 1: Disconnect the DisplayLink adapter and watch the video on the laptop screen.
If I have the DisplayLink adapter attached and active, I can’t watch on the laptop screen. This is different than when I used DisplayLink with a Windows laptop with dedicated graphics. If I needed to do something that didn’t work through DisplayLink (like WebGL), I could flip the laptop open and do it on the internal monitor while the external ones were still attached and active. Sometimes I could even start it on the laptop screen and then drag it to the DisplayLink-attached monitors and it continued to work.
WORKAROUND 2: Use two adapters and disconnect one.
This is a variation on #1. I also had a CalDigit USB-C to HDMI adapter on hand for travel. Instead, I plugged it into my Thunderbolt hub and connected my largest / highest-resolution monitor to that. The monitor connected by this method is not considered to be recording the screen.
In this configuration, I can technically have up to 4 screens running (2 HDMI via DisplayLink, 1 via the USB-C adapter, and the 1 internal), but can’t watch any protected content on any of them while the DisplayLink adapter is connected. If I disconnect the DisplayLink adapter, I can watch protected content on the monitor on the USB-C adapter and the laptop’s internal screen. I lose one port on my hub when I connect two adapters and still have to physically disconnect the DisplayLink adapter when I want to watch protected content (unless I use workaround zero).
I tried running a video in Chrome (on YouTube). The processor load averaged 12-15% on the “directly” connected monitor. Processor load increased to 17-20% when I moved the window to the DisplayLink-connected monitor. Idle tended to be 2-3% with both monitors connected. If you’re concerned about processor load or power usage, workaround 1 or 2 with the DisplayLink adapter disconnected will be your best bet.
WORKAROUND 3: Watch the videos in a browser in a virtual machine (VM) running a guest operating system on top of MacOS.
The guest operating system believes that the window in which it’s running is the primary monitor and doesn’t blank the video. I’d recently set up Windows 11 Pro for ARM on Parallels Desktop. Running the same YouTube video on Edge in Windows on a DisplayLink-attached monitor uses about as much CPU as running the same YouTube video in Chrome running natively in MacOS on the same monitor, AND it worked to run Udemy and Netflix. That said, Netflix in the browser on the Windows VM used more CPU overhead than YouTube did.
I also tried running it on the ARM version of Ubuntu that Parallels will let you automatically install, but it seems the encryption extensions for Firefox and Chromium are not available for the ARM version of Ubuntu (or I couldn’t find them). You literally do not even get the “enable DRM” checkbox in the Firefox settings. Maybe you can run an emulated x86_64 version of Linux and get Firefox or Chromium working, or perhaps compiling them yourself with flags for copy protection would deliver results, but that’s not a trivial amount of work.
WORKAROUND 4: Use Firefox. This is the last, because it’s been hit or miss with me. It’s worked twice for Udemy and never for Netflix. When it was working for Udemy, if I opened another tab and tried to play Netflix in it, Netflix wouldn’t display video and Udemy’s video stopped displaying. I’ve tried shutting down the laptop, restarting, and then going straight to Udemy in Firefox after that and it didn’t work. So I’m not sure what switch is flipped or how long its flipped for, but this is a serious “your mileage may vary” workaround.
And there you have it, four workarounds.
PLEASE NOTE The 14″ and 16″ M1 Pro and upcoming M2 Pro do not have this issue, because they natively support more than one monitor and even have built in HDMI ports, while Apple made a decision that the 13″ MacBook Pro and the MacBook Air would only support one external monitor. I made the choice to get the M2 Air and I think it’s “dead sexy.” I knew that I’d have to use DisplayLink to slot it in at my desk before I bought it. While I wish they could/would issue a firmware update that supports more monitors natively and I didn’t know about this “gotcha” of using DisplayLink with my Mac, I made a relatively informed choice and I’m living with it.