A computer-implemented method for updating a group-based communication interface (800-A) of a client device, wherein the group-based communication interface comprising a channel list pane (804, 806) indicating one or more group-based communication channels, the channel list pane (804, 806) including, when the client device is associated with a first group identifier, at least one internally shared communication channel that is only accessible to a first group of users associated with the first group identifier in a group-based communication system, the group-based communication interface further comprising a channel messaging pane for displaying objects exchanged over a selected group-based communication channel of the one or more group-based communication channels in the channel list pane, the method comprising: receiving, at one or more processors of the group-based communication system, an externally shared communication channel generation request, wherein the externally shared communication channel generation request includes the first group identification associated with the first group of users and a second group identification associated with a second group of users; in response to determining that the client device is associated with one of the first group identification or the second group identification, generating, in the channel list pane, an externally shared communication channel, corresponding to the externally shared communication channel generation request, in the channel list pane, the externally shared communication channel being associated with the first group identification and the second group identification; wherein the channel list pane further comprises an externally shared communication channel status indicator associated with the externally shared communication channel, wherein the externally shared communication channel is only accessible to the first group of users associated with the first group identification and the second group of users associated with the second group identification. receiving, at one or more processors of the group-based communication system, an externally shared communication channel generation request, wherein the externally shared communication channel generation request includes the first group identification associated with the first group of users and a second group identification associated with a second group of users; in response to determining that the client device is associated with one of the first group identification or the second group identification, generating, in the channel list pane, an externally shared communication channel, corresponding to the externally shared communication channel generation request, in the channel list pane, the externally shared communication channel being associated with the first group identification and the second group identification; wherein the channel list pane further comprises an externally shared communication channel status indicator associated with the externally shared communication channel, wherein the externally shared communication channel is only accessible to the first group of users associated with the first group identification and the second group of users associated with the second group identification.