I just opted out of suggestion/comment mails via the email link, to try out both the opt-out and opt-in workflow. Following the opt out link brought me to a SendGrid page where I could configure my preferences.
Assuming that I don’t have any mails containing the link, how do I opt back in? I couldn’t find any settings on observablehq.com that would even tell me that I’ve opted out / haven’t subscribed.
In the future, when we improve our email system to begin offering options (like a daily digest of Observable notifications, instead of live as comments and suggestions are sent), we’ll probably move all of the email notification configuration into the app.