Show Mode
Stops your show Mac embarrassing you mid-show
What it does
Show Macs fail in small, embarrassing ways. The display goes to sleep during a long hold. Someone's hand brushes a hot corner and Mission Control swooshes across the projector. A notification banner pops up on the LED wall, Night Shift turns the picture orange at sunset, or the cursor wanders out onto the output. Show Mode turns all of that off with one click in the menu bar (or ⌃⌥⌘S), and puts it all back with another.
The cursor fence keeps the pointer on your screens. Tick the ones the audience sees. With Accessibility switched on, any mouse movement heading onto one of them gets caught on the way and moved to the nearest place it's allowed, so the cursor never arrives. Without Accessibility it checks 120 times a second, pulls the cursor back and hides it near the edge, so nobody sees it cross. ⌃⌥⌘F pauses the fence for when you actually do need to drag something over.
Putting things back is the important half. Before Show Mode changes anything it writes down what was there, and at the end it only undoes its own changes, so a setting you'd already switched off stays off. If it gets quit, stopped by a launcher, crashes, or the Mac restarts mid-show, the next launch finds its notes and tidies up.
- Prevents display and system sleep, and optionally sleep on lid close for a laptop driving a projector
- Turns off Low Power Mode per power source, the screen saver, hot corners, Mission Control, App Exposé, their keys and gestures, and click-wallpaper-to-show-desktop, and, with your password, stops a mouse button opening Mission Control
- Do Not Disturb through two generated Shortcuts, since macOS gives apps no direct way to switch it
- Night Shift off with its schedule cleared, True Tone off, the light/dark appearance pinned, and f.lux, Shifty and Lunar quit and relaunched afterwards
- Blacks out the desktop wallpaper on every screen, including one plugged in mid-show, and brings the original back exactly — dynamic and aerial wallpapers and every Space included
- A cursor fence that keeps the pointer off chosen screens, remembered by make, model and serial across replugs. It never lets you block the last screen the cursor has, and asks before blocking the main display
- A screen layout lock: the main display, the clones and the extended screens stay as they were at the start. A new mirror is split back out, a split clone is put back, and when PowerPoint splits a clone for Presenter View its slides are moved onto the projector
- Mutes every app not allowed to play (macOS 26), so a mail chime or a browser tab cannot reach the PA, and silences the alert beep, interface sounds and the volume-key pop
- Pauses photo and media analysis and, with your password, Spotlight indexing and Time Machine; turns off apps' update checks and, optionally, automatic macOS and App Store updates
- Keeps crash dialogs, AirPlay, Keyboard Setup Assistant, ⌘Space and Stage Manager off the show, and names a remote session as it connects
- Pre-show Checks for what no app can switch off: a macOS update waiting, sync and backup apps, security software, heat, battery and Wi-Fi
- showmode://on, off, toggle, fence-on, fence-off, wallpaper-black and wallpaper-restore for Companion or a show-control script
- Every change journalled and restored — on end, quit, SIGTERM, or the next launch after a crash
Where it stands
Used on real shows, not just on my desk. v0.6.0's screen layout lock, holding clones and moving PowerPoint's slides, was tested against PowerPoint 16.112.3 on macOS 26.4.1 with virtual displays, not real ones yet, and the Mission Control fix through its real steps on the bench; neither has done a show. v0.5.0 added the audio muting, system sounds, background-work, interruption and remote-session guards and the Pre-show Checks menu. I've tested those on the bench on macOS 26.4.1 (the muting by recording what actually came out), but they haven't done a show yet, and neither have v0.4.0's privacy-dot and swipe-between-Spaces guards. The sleep, Low Power Mode, screen saver, hot corner, Mission Control, True Tone and Night Shift guards have been run end to end on macOS 26.4, and putting things back has been tested by ending the show, by killing the app and relaunching it, and by SIGTERM. On a real two-screen setup the cursor fence kept the pointer off a blocked screen with and without Accessibility, and the warnings about the main display and the last screen did what they say. The display lock split a new mirror back out, made the right display main again, gave up when something kept reverting it rather than fighting it all night, and put the original main display back after the show and after a crash. Do Not Disturb and appearance pinning both went on and came back off as they should, crash included. I haven't tried the display lock with AirPlay, Sidecar or DisplayLink screens, or seen a pinned appearance hold off a real evening switch, so if your show uses one of those screens, try it with them plugged in first. It's signed and notarised by Apple, so it opens normally.