Notifications turned off for Gitlab hosted repos?

I wanted to get updates about an omnibus issue (specifically Expand PgBouncer and Consul HA support to handle multiple databases in the same cluster (#5919) · Issues · / omnibus-gitlab · GitLab), but it seems the notification toggle is greyed out. In the Chrome inspector, I can find the error message Notifications have been disabled by the project or group owner. I tried several other issues at random (for example, Serve *in*directly from artifacts (#196) · Issues · / gitlab-pages · GitLab, Can't unshunt messages when arc is enabled and an initial Authentication-Results header has been added (#889) · Issues · GNU Mailman / Mailman Core · GitLab) and had the same problem. I couldn’t find any announcement about notifications being disabled and I don’t see anything specific to my account. Has something changed?