When Chrome initially supports expansion, any. crx extension file can be installed by dragging it to Chrome. Later, Chrome made the installation process of third-party extensions more complex. Drag and Drop will not allow installation. You must select third-party extensions in the settings, even this method allows some extensions to find loopholes. As a result, Chrome for Windows will completely restrict third-party extension installation from January 1, next January, but only Chrome Beta for Windows and Chrome Stable for Windows, any extensions that are not released to Chrome Web Store cannot be installed.
Of course, developers can still install extensions without packaging, or how to develop and test them? Then, commercial users can also allow administrators to configure third-party extensions for installation, but normal users cannot.
It seems that Chrome will be more rigorous than Android in the future. At least until now, Android still allows users to freely install the APK application from third-party channels. In addition, I don't know if this policy will be applied to Mac and Linux platforms. The first reason may be that there are too many malicious extensions for Windows users.