macOS Sonoma Drops Support for Legacy Mail App Plug-ins

With macOS Monterey in 2021, Apple introduced a MailKit framework that developers can use to build modern and secure extensions for the Mail app on the Mac. Extensions can be created to block content, perform message actions, improve security, and more.

General macOS Mail Feature
In turn, Apple said legacy Mail app plug-ins would stop functioning in a future macOS release, and it appears that time has now come. AltStore today said it confirmed with Apple during WWDC last week that plug-ins are not supported on macOS Sonoma, and that MailKit-based extensions are the only supported solution going forward.


While MailKit extensions are more secure, they have more limited functionality compared to legacy plug-ins, so not all plug-ins may live on as extensions.

Legacy plug-ins cannot be opened in the Mail app as of the first beta version of macOS Sonoma. The update will be released to the public later this year.

(Thanks, @aaronp613!)

Related Roundup: macOS Sonoma
Related Forum: macOS Sonoma

Popular Stories

iPhone 15 Pro Cameras

iPhone 17 Pro Max Will Be First Model to Feature Three 48MP Cameras

Thursday July 11, 2024 12:20 am PDT by
Next year's iPhone 17 Pro Max will feature an upgraded 48-megapixel Tetraprism camera for enhanced photo quality and zoom functionality, according to Apple analyst Ming-Chi Kuo. In his n-iphone-tetraprism-upgrade-ca62dd37e364">latest investor note published to Medium, Kuo said the key specification change would be a 1/2.6" 48MP CIS sensor, up from the 1/3.1" 12MP sensor expected to be used...
Beyond iPhone 13 Better Blue Face ID Single Camera Hole

10 Reasons to Wait for Next Year's iPhone 17

Monday July 8, 2024 5:00 am PDT by
Apple's iPhone development roadmap runs several years into the future and the company is continually working with suppliers on several successive iPhone models simultaneously, which is why we sometimes get rumored feature leaks so far ahead of launch. The iPhone 17 series is no different – already we have some idea of what to expect from Apple's 2025 smartphone lineup. If you plan to skip...
maxresdefault

Apple's AirPods Pro 2 vs. Samsung's Galaxy Buds3 Pro

Saturday July 13, 2024 8:00 am PDT by
Samsung this week introduced its latest earbuds, the Galaxy Buds3 Pro, which look quite a bit like Apple's AirPods Pro 2. Given the similarities, we thought we'd compare Samsung's new earbuds to the AirPods Pro. Subscribe to the MacRumors YouTube channel for more videos. Design wise, you could potentially mistake Samsung's Galaxy Buds3 Pro for the AirPods Pro. The Buds3 Pro have the same...
primeday2020 feature3

The Best Early Prime Day Deals on Apple Products

Saturday July 13, 2024 6:23 am PDT by
Amazon is soon to be back with its annual summertime Prime Day event, lasting for just two days from July 16-17. As it does every year, Prime Day offers shoppers a huge selection of deals across Amazon's storefront, and there are already many deals you can get on sale ahead of the event. Note: MacRumors is an affiliate partner with Amazon. When you click a link and make a purchase, we may...

Top Rated Comments

Max Webb Avatar
14 months ago
I didnt even know mail had plugin support full stop.
Score: 29 Votes (Like | Disagree)
redheeler Avatar
14 months ago
Over a decade on MacOS and this is the first time I heard that the Mail app supports extensions.
Score: 26 Votes (Like | Disagree)
erikkfi Avatar
14 months ago

While MailKit extensions are more secure, they have more limited functionality compared to legacy plug-ins, so not all plug-ins may live on as extensions.
Apple loves doing this kind of thing -- see how they ruined Safari extensions -- and then they wonder why their native apps' usage stagnates rather than grows.
Score: 16 Votes (Like | Disagree)
ddauerbach Avatar
14 months ago
I'm really going to miss the really really useful SmallCubed Mailsuite suite of plugins.
Score: 11 Votes (Like | Disagree)
BarryTheWebdork Avatar
14 months ago

I'm really going to miss the really really useful SmallCubed Mailsuite suite of plugins.
I registered just to upvote this. SmallCubed is apparently going to release its own mail client now. So... well done, Apple.
Score: 8 Votes (Like | Disagree)
zorinlynx Avatar
14 months ago
I still use Thunderbird because Apple Mail just isn't as capable. (Though I do use Apple Mail on my iPhone because the only mail client that was ever better on mobile was Sparrow and Google bought and killed that.)

People like to call Thunderbird "old" and "archaic" but E-mail hasn't changed much in 20 years. Thunderbird still does the job as well as it ever has, and they've recently started putting more development work into it so it will likely get even better moving forward.

Seriously, if you're a mail "power user", consider Thunderbird.
Score: 7 Votes (Like | Disagree)