Users of popular Mac desktop extension app Duet Display are being advised not to update to macOS 10.13.4, due to "critical bugs" that prevent the software from communicating with connected iOS devices used as extra displays.

When installed on a Mac and an iPad (or iPhone) and the two devices are connected using a Lightning cable or 30-pin connector, Duet allows users to extend their macOS desktop space on the Retina display of the iOS device. However, unspecified changes in the latest update to macOS High Sierra, released by Apple yesterday, causes the Duet client app to hang, and users are being advised to hold back from upgrading, at least for now.

duet display
Duet's developers are recommending that users contact Apple through the company's online bug reporting form to get the issue prioritized. In the meantime, the developers are "actively looking" into workarounds to reinstate Duet's functionality in macOS 10.13.4.

Duet Display is priced at $19.99 in the App Store, and unlocking the Pro features to turn the iPad Pro into a drawing tablet costs an additional $19.99 per year through an in-app subscription. Duet Display is available from the App Store. [Direct Link]

Update: Users of other desktop extension apps like Air Display and iDisplay are also reporting incompatibility with macOS 10.13.4. DisplayLink-enabled USB graphics devices are also reportedly affected. There's some speculation that Apple's added eGPU support in 10.13.4 is the underlying cause of the issues. We'll keep readers updated if we hear more.

Related Forum: macOS Mojave

Top Rated Comments

ouimetnick Avatar
72 months ago
Is it really a bug or did Apple intentionally change things that happened to break compatibility? Might not be a bug, and just the outcome of system changes to macOS
Score: 14 Votes (Like | Disagree)
rorschach Avatar
72 months ago
It never used to be this way with Apple, but unfortunately, this is what they’ve become.
Yes it did. People have ALWAYS said this.

I remember Snow Leopard wiping out people’s entire home folders. And 10.2.8 killing Ethernet. Etc.
Score: 12 Votes (Like | Disagree)
Bryan Bowler Avatar
72 months ago
I’ve been saying this for a year now and it still holds true: if you rely on your Mac for work, you can no longer trust Apple.

I have lost all faith in Apple’s ability to release software updates that do not break critical functions. There has not been a single major dot release in the last two years that has not broken something critical to my workflow. Not a single one.

After High Sierra is stable, I will not update my Macs for nearly a year until the next OS has stabilized. It never used to be this way with Apple, but unfortunately, this is what they’ve become.
Score: 12 Votes (Like | Disagree)
thadoggfather Avatar
72 months ago
Not a bug at all; 10.13.4 only supports displays which are directly connected by a GPU or by AirPlay.
Removing the clutter

Like battery estimates.

I still modify battery.menu to output battery
Time predictions on 10.12.6 even tho they scrapped it after .1 or .2 or something

Apple can’t come up w new features so new features has to be taking away features.
Score: 10 Votes (Like | Disagree)
TheMacDaddy1 Avatar
72 months ago
I’ve been saying this for a year now and it still holds true: if you rely on your Mac for work, you can no longer trust Apple.

I have lost all faith in Apple’s ability to release software updates that do not break critical functions. There has not been a single major dot release in the last two years that has not broken something critical to my workflow. Not a single one.

After High Sierra is stable, I will not update my Macs for nearly a year until the next OS has stabilized. It never used to be this way with Apple, but unfortunately, this is what they’ve become.
Hmmm....I use one every day for work (network engineer) and I would not have it any other way.

My only real complaint is when I have to use my USB to serial adapter to console into piece of equipment on site. USB-C to USB-A dongle, Keyspan USB-A to serial dongle, null modem cable to device or serial to ethernet to device. It is quite the frankestein setup in those cases....but it works every time.

I live in Omnigraffle Pro, Safari, Terminal, Secure CRT, mail, Excel, Word, etc.
Score: 7 Votes (Like | Disagree)
KPOM Avatar
72 months ago
('https://www.macrumors.com/2018/03/30/mac-desktop-extender-duet-bug-macos-10-13-4/')


Users of popular Mac desktop extension app Duet Display ('https://www.duetdisplay.com') are being advised not to update to macOS 10.13.4, due to "critical bugs" that prevent the software from communicating with connected iOS devices used as extra displays.

When installed on a Mac and an iPad (or iPhone) and the two devices are connected using a Lightning cable or 30-pin connector, Duet allows users to extend their macOS desktop space on the Retina display of the iOS device. However, unspecified changes in the latest update to macOS High Sierra, released by Apple yesterday ('https://www.macrumors.com/2018/03/29/apple-releases-macos-high-sierra-10-13-4/'), causes the Duet client app to hang, and users are being advised to hold back from upgrading, at least for now.



The critical issue was highlighted by Duet's ex-Apple developers in a blog post ('https://help.duetdisplay.com/faq/305404-macos-10-13-4-support') on the Duet support site, quoted from below.
Duet's developers are recommending that users contact Apple through the company's online bug reporting form to get the issue prioritized. In the meantime, the developers are "actively looking" into workarounds to reinstate Duet's functionality in macOS 10.13.4.

Duet Display is priced at $19.99 in the App Store, and unlocking the Pro features to turn the iPad Pro into a drawing tablet costs an additional $19.99 per year through an in-app subscription. Duet Display ('http://appshopper.com/productivity/duet-display') is available from the App Store. [Direct Link ('https://itunes.apple.com/us/app/duet-display/id935754064?mt=8')]

Article Link: Mac Desktop Extension Software Duet Display Rendered Inoperable in macOS 10.13.4 ('https://www.macrumors.com/2018/03/30/mac-desktop-extender-duet-bug-macos-10-13-4/')
This was an issue all throughout the beta period. I let the developer know early on.
[doublepost=1522414141][/doublepost]
I’ve been saying this for a year now and it still holds true: if you rely on your Mac for work, you can no longer trust Apple.

I have lost all faith in Apple’s ability to release software updates that do not break critical functions. There has not been a single major dot release in the last two years that has not broken something critical to my workflow. Not a single one.

After High Sierra is stable, I will not update my Macs for nearly a year until the next OS has stabilized. It never used to be this way with Apple, but unfortunately, this is what they’ve become.
To be fair, Duet Display is essentially a hack. It isn’t as if Apple intended the iPad to be used as an extended display for a Mac. If they did, they’d have built it in themselves.
Score: 7 Votes (Like | Disagree)

Popular Stories

iOS 17

Apple Releases iOS 17.0.1 and iPadOS 17.0.1 With Bug Fixes, Plus iOS 17.0.2 for iPhone 15 Models

Thursday September 21, 2023 10:28 am PDT by
Apple today released iOS 17.0.1 and iPadOS 17.0.1 updates for the iPhone and the iPad, adding bug fixes to the new software. The iOS 17.0.1 and iPadOS 17.0.1 updates come just a few days after Apple launched iOS 17 and iPadOS 17. The software, which is build 21A340, can be downloaded on eligible iPhones and iPads over-the-air by going to Settings > General > Software Update. There is a...
iPhone 16 Mock Header With Dynamic Island

Skipping the iPhone 15 Pro? Here's What's Rumored for iPhone 16 Pro

Friday September 22, 2023 9:29 am PDT by
Are you skipping the iPhone 15 Pro and waiting another year to upgrade? If so, we already have some iPhone 16 Pro rumors for you. Below, we recap new features rumored for the iPhone 16 Pro models so far:Larger displays: The iPhone 16 Pro and iPhone 16 Pro Max will be equipped with larger 6.3-inch and 6.9-inch displays, respectively, according to Ross Young, CEO of Display Supply Chain...
Update Your iPhone 15 to iOS 17

Warning: Update Your iPhone 15 to iOS 17.0.2 Before Transferring Data From Another iPhone

Friday September 22, 2023 6:36 am PDT by
If you are unboxing an iPhone 15, iPhone 15 Plus, iPhone 15 Pro, or iPhone 15 Pro Max today, make sure to update the device to iOS 17.0.2 before transferring data to the device from another iPhone, or else you might encounter issues. iOS 17.0.2 is only available for the iPhone 15 lineup. Apple says the update fixes an issue that may prevent transferring data directly from another iPhone...
Apple Watch Ultra 2 double tap gesture 230912

watchOS 10.1 to Enable Apple Watch's New 'Double Tap' Gesture

Thursday September 21, 2023 12:52 pm PDT by
The new Double Tap gesture for the Apple Watch Series 9 and the Apple Watch Ultra 2 will be enabled starting with watchOS 10.1, according to Marques Brownlee, host of the popular tech-focused YouTube channel MKBHD. The first beta of watchOS 10.1 will likely be available by next week, and Apple announced that the software update will be released next month. Brownlee shared his impressions...
emojipedia 15 1 emoji

Emoji Coming to Future iOS 17 Update Include Shaking Head, Brown Mushroom, Lime, Phoenix and More

Tuesday September 19, 2023 12:43 pm PDT by
As Apple was announcing new iPhone models last week, the Unicode Consortium was officially approving new emoji characters that are set to be added to smartphones starting in 2024. Mockup of new emoji from Emojipedia Approved Unicode 15.1 emoji include phoenix, lime, an edible mushroom, shaking head vertically (as in a "yes" nod), shaking head horizontally (a "no" head shake), and broken...
iPhone 15 Pro Fingerprints

Apple Says Fingerprints Can 'Temporarily Alter the Color' of iPhone 15 Pro's Titanium Frame

Thursday September 21, 2023 2:48 pm PDT by
In a support document updated today, Apple indicates that fingerprints might "temporarily alter the color" of the titanium frame on the iPhone 15 Pro and iPhone 15 Pro Max. Fortunately, Apple says this is not a permanent condition, as the fingerprints can be wiped off just like on any other iPhone to restore a clean finish. "For iPhone 15 Pro and iPhone 15 Pro Max, the oil from your skin...