With macOS Mojave support being one of the new features of Xojo 2018r3, you might want to polish your desktop UIs by incorporating the new dynamic color constants. While Xojo supports only a selection of them, CSTrueColors from Ulrich Bogun has all 50+ as dynamically buffered Xojo Colors which means they are cached until a Dark Mode change or a change of the selection/AccentColor happens.
To make xplatform development easier, you find the same colors on Windows too, and on this platform selection and high contrast mode changes are registered, but not the current Windows Dark Mode.
convert Xojo pictures to macOS template images which change their brightness automatically
insert pictures and templates into some of the most commonly used desktop controls.
some color conversion methods and Apples new System Effects
macOS VisualEffectViews as custom controls (Mojave types)
A demo version is available here, and here is the documentation.
The paid version comes as unencrypted source code for 12.50 see the license info.
There is no renewal fee, and all version 1 updates will be free for buyers.