LynxHub is open-source and not currently code-signed with a commercial Apple Developer certificate. macOS will warn you about an unsigned developer when you open it.

1. Right-click (or Control-click) the application in Finder.
2. Select Open from the context menu.
3. Click Open Anyway in the confirmation dialog.
4. You only need to do this once. The app will open normally hereafter.

If you are using the portable AppImage format on Linux, you must allow the file to run as an executable before starting it.

chmod +x LynxHub-3.5.5-linux-Portable_x86_64.AppImage

Alternatively: Right-click the file, select Properties, go to the Permissions tab, and tick “Allow executing file as program”.