Run in Terminal

codesign --force --deep --sign - /Applications/name.app

Requisite: Xcode or the Apple Command Line Tools To install, execute

xcode-select --install

in the terminal emulator of your choice, and the macOS GUI will give you the option to install Xcode (from the MacApp Store) or the CLTs. If you install Xcode, launch it at least once to complete the installation and agree to thelicense.

Alternatively, you can use CodeSigner to sign some apps.

Installation instructions:

Downloaded CodeSigner, then mount the DMG volume
Copy CodeSigner.app from the mounted DMG volume into one of your applications paths; recommended:~/Applications/Utilities/
If you are using macOS Finder or a similar application with Services support as your main file manager,double-click the CodeSigner workflow: a window titled Quick Action Installer will appear asking you if you wantto install it; click Install. You can assign a keyboard shortcut to the Quick Action in System Preferences >Keyboard > Shortcuts > Services > Files and Folders > CodeSigner
If you also want the ability to manually run CodeSigner in a terminal emulator—example:
Codesigner /Applications/Parallels\ Desktop.app
Copy the codesigner shell script into your \$PATH, e.g. /usr/local/bin/
On Mojave please allow CodeSigner to control System Events; this is necessary for GUI prompts to work viaAppleScript

Or run

- codesign --force --deep --sign - /Applications/Your App Name.app

in terminal, It will try to force sign the app and give you permission to run it.

Open App Crash Self Signature