[macOS 26.4.1 Tahoe + M5] Menu bar icon never appears; BD fails to control brightness (Dell marked disconnected, NSStatusItem visibility loop)

[mohamorui]

Environment

• macOS: 26.4.1 (25E253) Tahoe
• Chip: Apple M5 (arm64)
• BetterDisplay: 4.2.3 (installed via brew install --cask betterdisplay)
• Signed: Developer ID Istvan Toth (299YSU96J7), notarization stapled

Displays

• Built-in: Color LCD 2560x1664 Retina (has notch)
• External: DELL S2722DC 2560x1440 @ 75Hz via USB-C
• System sees both Online. (Mirror state varies — reproduced in both mirrored and extended.)

Issue 1 — Menu bar icon never appears

Symptoms

• After install, no BD icon shows in the menu bar.
• Pref hideMenuIcon = false, NSStatusItem VisibleCC Item-0 = 1 — BD believes the item is visible.
• betterdisplaycli get --identifier=all returns:

  Failed. Request timed out. Host app might not be running or is not accepting notifications.
  (but the BD process is alive)

• log show --process BetterDisplay shows a tight loop of NSStatusItemChangeVisibilityAction between BD and ControlCenter roughly every 200 ms — BD keeps trying to show the status item, something keeps hiding it, forever.
• Two BetterDisplay processes are spawned at login simultaneously (one via appStartAtLogin, another duplicate) — unclear where the second comes from.

Issue 2 — Brightness control via BD does not work

Symptoms

• BD cannot drive brightness on the DELL S2722DC (standard DDC/CI monitor, worked in BD 4.x on previous macOS).
• BD internal state for the Dell:

  connected@Display:3 = false
  isUnavailable@_registration_DDCController-DDCController@Display:3 = true
  

  BD marks the external display as disconnected even though macOS sees it Online, so the DDC controller is never registered and brightness adjustments silently do nothing.
• Because Issue 1 hides the menu bar icon, there is no UI path to re-trigger display detection from the user side either.

Already tried (nothing fixes it)

• Full uninstall: removed ~/Library/Application Support/BetterDisplay, ~/Library/Preferences/pro.betterdisplay.BetterDisplay.plist, ~/Library/HTTPStorages/pro.betterdisplay.BetterDisplay*, ~/Library/Caches/pro.betterdisplay.BetterDisplay*
• Fresh brew install --cask betterdisplay
• xattr -rd com.apple.quarantine /Applications/BetterDisplay.app
• lsregister -f to re-register with LaunchServices
• arch -arm64 open to ensure native run
• Accessibility + Screen Recording TCC permissions granted
• Full system reboot
• Killed all menubar-hider apps (Hidden Bar)

Request

• Is this a known regression on macOS 26.4.1 (Tahoe) + Apple silicon M-series?
• Is there a way to reset BD's internal display registry so it re-detects the DELL?
• Is the duplicate-process-at-login also known?

Happy to provide sysdiagnose / further logs if helpful.

[waydabber]

I don't know of any issue regarding 26.4.1.

I recommend backing up settings and then doing a settings reset (while the app is not running). Run this in Terminal:

defaults delete pro.betterdisplay.BetterDisplay

The duplicate process at login is not normal. Are you sure you don't have the app installed somewhere as a copy and starting as well somehow?

[mohamorui]

Update after the reset you suggested:

Progress

• defaults delete pro.betterdisplay.BetterDisplay done (with app killed first).
• Dell S2722DC is now detected — connected@Display:3 = 1, DDC registration is no longer marked unavailable.
• Brightness on the Dell can be driven via the URL scheme / CLI, so the DDC path itself works.

Duplicate-process-at-login: root cause found

• System had BD registered via SMAppService (Identifier: 2.pro.betterdisplay.BetterDisplay, Generation: 2) and the BD pref appStartAtLogin = 1 was also active. Both autostart paths fired → two processes. After the reset only one BD process spawns on login.

Menu bar icon: still never appears
On every launch after reset, BD's plist ends up as:

hideMenuIcon = 1
"NSStatusItem VisibleCC Item-0" = 0

The VisibleCC Item-0 = 0 looks like the system reporting back that the status item is NOT visible, after which BD seems to flip hideMenuIcon to 1 as a fallback. Meanwhile ~/Library/Preferences/com.apple.controlcenter.plist has no entry at all for a BD status item (only Battery / Sound / Clock / BentoBox-0 / FocusModes are registered). So the NSStatusItem registration for BD appears to be silently rejected by macOS 26.4.1.

With no menu bar icon there's also no UI path to toggle hideMenuIcon back — a URL scheme to open Preferences or forcibly show the status item would unblock users in this state.

Environment note you asked about

• Only one copy of BD on the system: /Applications/BetterDisplay.app (from brew install --cask betterdisplay). mdfind + manual scans confirm no other copies.
• MonitorControl 4.3.3 is also installed at /Applications/MonitorControl.app but is not running and is not set to autostart. Its SMAppService entry still references a now-deleted copy in ~/.Trash/ (file:///Users/.../.Trash/MonitorControl.app/), with a MonitorControlHelper child entry marked enabled — stale leftovers, but since MC isn't running I don't think they're interfering with BD's status item. Mentioning in case it matters that both MC and BD register status items under the Item-0 key.
• No Bartender / Hidden Bar / Ice / Dozer running.
• Full system reboot done; same behavior.

Is there a Tahoe-specific entitlement or signing change required for NSStatusItem registration that BD 4.2.3 might not declare yet?

Thanks for building BetterDisplay (and MonitorControl before it) — these have been indispensable tools for external monitor users on macOS. Really appreciate your time looking into this, and happy to run any additional diagnostics you need.

[waydabber]

Hmm. I am not sure what could be the issue with the icon. The app has an observer for the menu icon and also has icon removal enabled and when it is removed by the user (or a third party), it acknowledges that and turns the hideMenuIcon = 1.

You should still be able to reach App settings by simply relaunching the app and then turn the menubar extra icon on under the Menu pane. However if whatever is removing the menu does it again, the option will be turned off.

If you start the app using the -v option from Terminal, you should get notified when something outside of the app removes the menu icon (it will show a menu icon visibility change log entry).

[waydabber]

A possible answer can be found here regarding the menu bar icon: #5754 (comment)