Sunday, September 13, 2020

Getting Mailvelope on Chrome to use GnuPG on macOS

Mailvelope is a browser add-on that helps use GPG encryption and signing on webmail systems like Gmail. Here are the steps on macOS (tested with "Big Sur") to get Mailvelope to use the GnuPG backend.

Install gpgme via Homebrew: brew install gpgme This will install gpgme-json in /usr/local/bin by default. 

Create a file called gpgmejson.json in 
"~/Library/Application Support/Google/Chrome/NativeMessagingHosts"
with the following contents:

    "name": "gpgmejson",
    "description": "Integration with GnuPG",
    "path": "/usr/local/bin/gpgme-json",
    "type": "stdio",
    "allowed_origins": [

Now in Mailvelope > Options > General, GnuPG will show up as the encryption backend. 


1 comment:

Gwyneth Llewelyn said...

This is awesome!

Unfortunately, I'm not using Chrome — just Chromium-based browsers such as Brave and Microsoft Edge. Both have very similar directory structures under ~/Library/Application Support, and both have the NativeMessagingHosts directory.

However, they seem to have some difficulty in locating this JSON file. In other words, Mailvelope is still clueless about the existence of GnuPG and/or gpgme in either of them.

I've also tried to follow the instructions given for Firefox, but I had no luck there.

All that remains is to get it working under Safari... heh, I know that Safari is unsupported. Alas!

Thanks anyway!