In addition to its rounded corners and Liquid Glass, macOS 26 Tahoe brings substantial change in app icons. These follow the move to squares with rounded corners brought in macOS 11 Big Sur, and now enforce that outline on all apps, including Apple’s. The result is that icons of irregular shape, such as those used by SilentKnight and the rest of my apps, will be intentionally shamed by reduction in size and placement in a sin bin of a grey square with rounded corners. Although some developers are busy implementing workarounds, Apple has made it clear that it expects conformity with this new style.

While app designers and developers have to work within those stricter constraints, Tahoe opens up new user options in the display of app icons, extending the light and dark appearances that have been standard since macOS Mojave seven years ago. System Settings now provide a choice of four rendering modes for the display of icons and widgets, in dark, clear, tinted and default, with a further option for tinting colour.

To accommodate these changes, Tahoe has a new app aimed at those designing and implementing app icons, Icon Composer, free for anyone to download from here, and compatible with macOS Sequoia and later. Although not intended for customising icons within existing apps, it provides insight into these new design constraints and rendering modes.

In the past, app icons have been able to distinguish themselves by their form, colour and internal details, with the first two becoming dominant as their size is reduced in a heavily loaded Dock. By enforcing a uniform outline, Apple’s new interface style makes this task harder. I already have difficulty distinguishing Messages, FaceTime, even Numbers and Archive Utility, which in turn forces me to separate them in the Dock, and I still occasionally open the wrong app as a result. Other confusions have become common: Xcode, Developer and several third-party app icons are also hard to distinguish when at small size. Apple clearly hasn’t listened to criticism from users and developers, and has only made this worse in Tahoe.

We’re therefore left to make the best we can within these new rules. My recent redesigns for my own apps are an initial attempt to make their icons as distinct as I can, and to remain so in older versions of macOS at the same time.

I’ll start with the new icons for Mints, SilentKnight and SystHist, seen in the Dock in existing macOS in light mode.

and dark mode

Here, with the addition of XProCheck, are four of the many possibilities in Tahoe, first in light mode with default rendering

then in dark mode, again with default rendering

Clear rendering decolourises them into monochrome with valuable contrast

but tinted rendering makes their details even harder to read

As I gain experience in using Icon Composer, and understand better how Liquid Glass may be able to enhance the results, I intend improving on these. For the time being, though, what you see in these updated versions works better across all recent versions of macOS and Tahoe. As with other features of macOS 26, these will take further tuning on my part, and patience on yours. Please bear with me in the coming weeks and months.