Help and troubleshooting

The build isn't notarized by Apple, so Gatekeeper blocks a plain double-click. Right-click Keron.app and choose Open instead, then confirm. You only have to do this once.

If that still doesn't work, clear the quarantine flag in Terminal:

xattr -dr com.apple.quarantine /Applications/Keron.app

That one's deliberate. Notification Center's own clock panel is left as macOS drew it — restyling it would break the panel rather than improve it. Every actual notification banner still goes through your design.

Keron stores placement per display, so each monitor has its own position and offsets. There are two settings that override that:

• Target display pins every banner to one specific monitor.
• Follow active screen puts banners on whichever screen you're currently working on.

Also note that macOS can hand out a different identifier for a monitor after you unplug and reconnect it, in which case that display starts from the default placement again.

Group membership is picked by app, but banners are matched by the name macOS reports at the moment the notification fires — and a few apps report a name that doesn't match any of the names in their app bundle.

Keron fixes this on its own: the first notification from such an app teaches the group the real name, and every one after that is matched correctly. If a group looks like it's being ignored, trigger one notification from the app and try again.

Also worth checking: an app can only belong to one group. Adding it to a second group removes it from the first.

A test banner is drawn by Keron directly, so if it doesn't appear the problem is placement rather than permissions — it may be positioned off the edge of the screen or on another display. Reset the position to Top Right with zero offsets and try again.

Check the auto-dismiss setting too. A very short duration can make a banner vanish faster than you notice it.

Use Share Theme… in the editor. Keron writes a single .json file containing the whole design — the box, every element, the animation, and the actual audio and image data for any custom sound or background you used. The person you send it to opens it with Import Theme… and gets exactly what you built, with nothing else to install.

A theme is one design. To move your entire setup — all your groups, placements and presets — export your settings instead.

That's by design. Closing Keron's window drops its Dock icon and its place in Cmd-Tab, but the app keeps running in the background so your banners keep working. Open it again from the menu bar icon, or just launch Keron from Spotlight — the window and Dock icon come straight back.

If you also hid the menu bar icon, Spotlight is the way back in.

Reset All Settings in Keron restores every default — designs, placements, groups and preferences — without touching the app itself. If you want to keep what you have first, export your settings before resetting.

No. Keron contains no networking code, so there is nothing to send and nowhere to send it. Your notification content is read to redraw the banner and discarded when it dismisses.

The privacy page covers this in detail.

Keron 1.0 requires macOS 27.0 or later, on Apple silicon or Intel. The way macOS draws notifications changes between releases, so older versions aren't supported.