Bug: BP Nouveau accept invitation error

[meijioro]

I get a “There was a problem performing this action. Please try again.” notice error when I try to click the “Accept Invitation” button on one of the groups on the group page (mydomain.com/groups).

This seems to be only happening when using Nouveau. I tried removing all plugins and using Twenty Seventeen or Twenty Twenty theme. Both still give the error when I try to accept. When I try using Legacy instead, it works fine. It’s just Nouveau is broken. And it’s only where all groups are listed on the "/groups" page. Accepting in my manage profile area (the buttons are Accept & Reject are listed) works fine.