dwarvesf/hidden v1.11 on GitHub

Hiding works again on macOS 27 (#360).

What's new

macOS 27 support. macOS 27 drops status items that get too wide, so Hidden Bar's old trick of widening a spacer stopped hiding anything. This build asks macOS to hide the icons instead, using the same mechanism as the system's exam lockdown mode. The arrow is now the divider: ⌘-drag an icon to the left of the arrow to hide it, or to the right to keep it.
Hover to expand, off by default. Turn it on with defaults write com.dwarvesv.minimalbar hoverToExpand -bool true.
Right-clicking the arrow opens the menu.

Hidden icons no longer leak onto wider external monitors, and the width resets when you plug in a display.
Auto-collapse waits while your pointer is in the menu bar, and it no longer closes Preferences.
Icons ⌘-dragged off the bar come back at launch.
Turning on the always-hidden section no longer gives you an invisible separator.
Memory and observer leaks in the tutorial view are fixed.
Launch at login now uses SMAppService, and the old helper app is gone.

Hidden Bar needs Accessibility permission to see where your icons are. Without it, the bar stays expanded.
It relies on a private Apple framework, so a macOS update could break it. If that happens, Hidden Bar leaves the bar expanded rather than hiding the wrong things.
Run it from /Applications. A copy anywhere else hides its own arrow.
Hiding works per app, so an app with several icons hides or shows all of them together.
The clock, Wi-Fi, Sound and Control Center always stay visible.
This download isn't sandboxed. The App Store version is, and the sandbox blocks this approach, so the App Store version still can't hide on macOS 27. If you have it installed, quit and delete it before installing this one.

Nothing changes on macOS 26 and earlier. Requires macOS 13 or later.