By default, Gpg4win installer doesn't include Browser integration option. Therefore, when installing Gpg4win with Chocolatey or with the /S option, the component is not installed, and Mailvelope's native messaging feature cannot be used.
I've checked the Compendium's Automatic installation of Gpg4win, but didn't see anything to add in the gpg4win.ini file related to this component.
Possible solutions:
- Add an option to the installer or gpg4win.ini
- Install the Browser integration option by default
Related issue: https://github.com/mailvelope/mailvelope/issues/628#issuecomment-446521213
Gpg4win: v3.1.5
Windows: 10 v1803