mitmproxy/doc-src/certinstall/osx.html

How to install the __mitmproxy__ certificate authority in OSX:

<ol>

    <li>Open Finder, and double-click on the mitmproxy-ca-cert.pem file.</li>

    <li>You will be prompted to add the certificate. Click "Always Trust": 

        <img src="@!urlTo('osx-addcert-alwaystrust.png')!@"/>
    </li>

    <li> You may be prompted for your password. You should now see the
    mitmproxy cert listed under "Certificates".</li>
</ol>