TinkerTool

TinkerTool is a window onto the preferences Apple built into macOS and then left out of System Settings: Finder showing full paths, Dock animation speed, where screenshots land and in what format, font smoothing, Safari and Mail internals. Marcel Bresink has shipped a matching build for every macOS release since 2003, and 11.71 covers macOS 26 and 27.

Two decisions make it worth trusting. Everything it changes is user-level, so it never asks for an admin password and never touches system components — a macOS update will not undo or break what you set. And every switch can be put back, either to Apple's default or to whatever state it was in before you opened the app. That is more than you get from pasting a command into Terminal and hoping you noted the old value.

The limit is genuine. TinkerTool can only surface what Apple already wrote, and Apple removes hidden preferences between releases, so something you used two systems ago may simply be gone. Settings apply to your account only, not to other users and not to the login window.

If you were after disk cleanup, log inspection or permissions repair, that is Bresink's other app, TinkerTool System, and it is licensed separately. Free TinkerTool is the settings panel and nothing more — which, for most people asking, is the part they actually wanted.