[rfced] Section 6.2: Does "they have" refer to "a user" (in

[ekr-cibot]

[rfced] Section 6.2: Does "they have" refer to "a user" (in
which case "they have" should be "the user has") or something else?

Original:
Applications can strengthen connectivity among parallel groups by
requiring periodic key updates from a user across all groups in which
they have membership.

[ekr-cibot]

tagging @lbartholomew-rpc for awareness