Show Mode is a menu-bar app that locks a Mac down for a show. One click (or ⌃⌥⌘S) stops the machine from sleeping, stops the things that slide over the screen when an operator’s hand slips — hot corners, Mission Control, the click-to-show-desktop wallpaper, notification banners — stops the colour of the picture drifting with the time of day, and keeps the mouse cursor off the screens the audience is looking at. A second click puts every setting back exactly as it was.
Before you rely on this: the power, screen-saver, hot-corner, Mission Control, True Tone and Night Shift guards were run end to end on a MacBook Pro running macOS 26.4, and restoring was checked three ways: ending show mode, killing the app outright and relaunching it, and stopping it with SIGTERM. Every setting came back. The wallpaper blackout was checked the same three ways on macOS 26.4.1, but only on its own (not as part of a full show-mode start) and only on one display.
Checked on a second screen (v0.3.0): with a real extended display attached (a Roland USB video output) and a virtual one, the cursor fence held a gliding pointer at the edge with Accessibility granted and pulled back a pointer warped onto the show screen; pausing and resuming it worked. The display lock split a mirrored display back to extended, made the locked display main again after something else took over, gave up after repeated reversals instead of fighting, and put the original main display back at the end of the show and after the app was killed mid-show.
Do Not Disturb (checked 2026-09-29, macOS 26.4.1): both shortcuts ran and switched Do Not Disturb on and off, and show mode turned it on at start, off at the end, and off again on the next launch after being killed mid-show.
Checked 2026-09-29 (v0.3.1): the fence without Accessibility, which pulls the pointer back within one mouse step and hides it near the show screen, and hiding the cursor from a background app; the main-display warning, both its buttons, and the rule that the last screen cannot be blocked; and pinning the light/dark appearance, which System Settings showed switching from Auto to the showing appearance and back, including after a crash.
Not yet checked: the display lock with AirPlay, Sidecar or DisplayLink screens, which may not answer the mirroring call the way a cabled display does; and a real sunset under a pinned appearance (the pin itself was checked, but not an evening switch it holds off). Try it on the show machine, with the show screens connected, before a show depends on it. Released at v0.3.1 (beta).
This codebase was created with AI assistance, directed and reviewed by a human author.
Install
Download the .dmg from the latest release,
open it and drag Show Mode to Applications. It is signed and notarised by Apple and
opens normally. Or with Homebrew:
brew tap stoatworks-labs/tap
brew trust --tap stoatworks-labs/tap
brew install --cask showmodeShow Mode needs macOS 13 or later and runs on Apple silicon and Intel Macs. It lives in the menu bar as a pair of theatre masks and has no Dock icon.
Starting and ending a show
Click the masks and choose Start Show Mode, or press ⌃⌥⌘S anywhere. The masks turn solid red while show mode is on. End Show Mode (or ⌃⌥⌘S again) puts everything back.
If something could not be applied — Do Not Disturb before its shortcuts are installed, a cancelled password prompt — a short note appears under the menu bar for a few seconds and stays listed in the menu, marked ⚠︎, until the show ends. It deliberately does not use a notification: show mode may just have silenced them.
What it turns off
Every guard can be switched off in What Show Mode Disables. A change there applies at the next start.
| Guard | What it does |
|---|---|
| Prevent display & system sleep | Holds a power assertion, the same way a video player does. It goes away with the app, so a crash cannot leave a Mac that never sleeps. |
| Prevent sleep on lid close | Sets pmset disablesleep, so a laptop driving a projector keeps going with its lid shut. Off by default because it asks for your password on every start and end. |
| Turn off Low Power Mode | Only if it is on, per power source (battery and mains separately). Asks for your password once. |
| Disable screen saver | Sets the idle time to never. |
| Disable hot corners | Sets all four corners to do nothing, and restarts the Dock so it takes effect. |
| Disable Mission Control, Exposé & gestures | Turns off Mission Control and App Exposé, including their keys, and the swipe and pinch gestures for Mission Control, App Exposé, Show Desktop and Launchpad. Restarts the Dock. |
| Disable click-wallpaper-to-show-desktop | Stops a stray click on the desktop sweeping every window aside. |
| Black out desktop wallpaper | Paints the wallpaper black on every screen, including one plugged in mid-show, so an extended desktop never shows your wallpaper on the projector. The original comes back exactly, dynamic and aerial wallpapers and every Space included. |
| Do Not Disturb | Turns on Do Not Disturb, so no notification banner lands on an output. See Notifications. |
| Disable Night Shift | Turns Night Shift off and clears its schedule, so it cannot come back on at sunset mid-show. |
| Disable True Tone | Stops the built-in display re-tinting itself to the room’s light. |
| Pin light/dark appearance | If the appearance is set to Auto, switches it to whichever of Light or Dark is showing now, so it cannot flip at sunset mid-show. Auto comes back when the show ends. |
| Quit colour-shift apps | Quits f.lux, Shifty and Lunar if they are running, and opens them again afterwards. |
| Fence cursor off show screens | See Keeping the cursor off the show screens. |
| Lock main display & keep new screens extended | See Keeping the display arrangement. |
Starting show mode restarts the Dock once, which makes the Dock and the menu bar flicker for a moment. Do it before doors, not during a cue.
Keeping the cursor off the show screens
Under Keep cursor off, tick each screen the audience sees. Screens are remembered by their make, model and serial number, so the choice survives unplugging them and restarting. The screen with the menu bar is marked so you can tell the built-in panel apart.
The cursor always keeps at least one screen. The last unticked screen cannot be ticked, so on a Mac with only one screen there is nothing to tick. Ticking the main display — the one with the menu bar, Show Mode’s own menu and the Dock — asks first, because during the show you could not reach any of those with the mouse. Usually the better fix is to choose the operator screen under Main Display, so the menu bar stays there for the show.
How hard the fence is depends on one permission:
- With Accessibility granted (Setup → Grant Accessibility for a hard cursor fence): every mouse movement that would land on a show screen is caught on its way in and moved to the nearest point on a screen you can use. In testing, a pointer glided at a show screen in 10-pixel steps stopped dead at the edge; in 2 of 12 runs one sample caught it a few pixels over for less than one step (under 10 ms) before it was pulled back.
- Without it: Show Mode checks the cursor 120 times a second and moves it back. In testing, one movement of the mouse — about 10 pixels at a normal pace, 60 on a fast flick — could land on the show screen for up to 8 ms before being pulled back. So it also hides the cursor within 48 pixels of a show screen: an ordinary approach is never drawn on the other side, and only a flick that starts further away than that can show for an instant. Turn the hiding off with Hide cursor if it reaches a blocked screen if you would rather see it. Granting Accessibility is the better answer on a show machine.
⌃⌥⌘F pauses the fence (and again to resume) when you need to reach a show screen on purpose — to drag a window onto it, say. The masks change to a circle while it is paused.
The fence also stands down on its own rather than trap you: if every screen is ticked, or the only screen you left unticked is unplugged, it does nothing until that changes.
Keeping the display arrangement
With Lock main display & keep new screens extended on (it is by default), show mode holds the display arrangement the show started with.
The main display stays put. The main display is the one with the menu bar and the Dock, and it is where new windows and many apps’ dialogs appear. Choose it under Main Display, or leave that on Whichever is main at start. If anything makes a different screen main during the show — a display reconnecting, a projector macOS remembers from another venue — show mode moves it back within about a second. The arrangement itself is kept: the screens stay where they are relative to each other, only which one carries the menu bar changes back. If the display you chose is not connected at start, show mode says so and makes it main the moment it appears.
New mirrors become extended. Whatever is mirrored when the show starts is taken as deliberate — a confidence monitor showing the output, say — and left alone. Any screen that starts mirroring during the show, whether a newly plugged-in projector that macOS decides to mirror or a stray ⌘F1, is split back out to an extended display about a second later.
Changing which display is main makes every screen blink for a moment, the way it does in System Settings. Show mode only does it when something else has already moved the main display, but choose the main display before doors rather than mid-cue. If something keeps undoing the arrangement — four corrections inside twenty seconds — show mode stops fighting it, says so in its menu, and leaves the screens alone for the rest of the show.
When the show ends, the display that was main before it becomes main again. Screens that were split out of a mirror stay extended: the mirror was macOS’s guess, not yours.
Choosing a main display that is also fenced off puts the menu bar out of the cursor’s reach, so show mode warns you at start. ⌃⌥⌘F pauses the fence.
Notifications
macOS gives apps no way to switch Do Not Disturb on, so Show Mode uses two tiny shortcuts that do it for it. Choose Setup → Install Do Not Disturb shortcuts. After about half a minute Shortcuts asks you to add Show Mode Focus On and Show Mode Focus Off; add both. From then on show mode runs them itself. Until they are installed, show mode skips Do Not Disturb and says so.
The shortcuts switch the built-in Do Not Disturb Focus, not any custom Focus you have made. Whatever that Focus allows through — people or apps you have allowed in System Settings → Focus → Do Not Disturb — still gets through, so check its allow list on the show machine.
Driving it from somewhere else
Show Mode answers a URL scheme, so Companion, a show-control script or a Terminal can drive it:
open showmode://onThe others are showmode://off, showmode://toggle, showmode://fence-on,
showmode://fence-off, showmode://wallpaper-black and showmode://wallpaper-restore.
Blacking out the wallpaper on its own
Black Out Wallpaper in the menu (or showmode://wallpaper-black) blacks out every
screen without starting show mode — for a rehearsal, or a desktop share. Restore
Wallpaper puts it back and leaves everything else alone. Ending show mode, quitting, or a
relaunch after a crash also restores it.
What it did
Show mode keeps a plain log of what it changes at ~/Library/Logs/ShowMode.log — the fence
coming on and in which mode, and every correction the display lock makes. Console.app opens
it.
Putting things back
Before Show Mode changes anything it writes down what was there, in
~/Library/Application Support/ShowMode/journal.plist. Ending the show restores exactly
those values — a setting you had already switched off yourself stays off. The same happens
when you quit, when a launcher stops the app, and if the app crashes or the Mac restarts
mid-show: the next launch finds the journal, restores it, and tells you it did.
Launch at Login (in Setup) is worth turning on for a show machine, so a restart mid-show is followed by a clean restore.
Running it from source
git clone https://github.com/stoatworks-labs/showmode
cd showmode
scripts/build-app.shThat builds a universal dist/Show Mode.app. swift build alone gives a bare executable
for development; .build/debug/ShowMode --status prints what it can see without changing
anything.