If you’ve created a web extension that works in a browser other than Safari, you can deploy it in Safari by using the Safari web extension converter.
Prerequisites: Safari 14 and Xcode 12
To run the converter, open the Terminal app and run the safari-web-extension-converter command, providing the path for your existing extension files.
xcrun safari-web-extension-converter /path/to/extension
The converter asks you for several pieces of information, to convert your existing extension interactively.
After you confirm your selections, the converter generates and opens your new Xcode project. The converter reports any manifest keys that the current version of Safari doesn’t support.
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