macOS chat window errors when viewing messages from deleted user

I introduced a friend to keybase a while ago and they've decided they don't use it enough to want the account around right now so they deleted their account using the web interface. However I now have errors in my chat window because keybase is trying to load the messages from a deleted user.

The error message makes sense and says clearly that the reason is that the user was deleted, but it feels a bit like a system error being displayed which may not be intended.

Here's a screenshot of everything I see, I've redacted other conversations in black and my friends user name in red for privacy.

Version & Platform details

Platform Information:
    OS:        darwin
    OS vers:   10.12.5-16F73
    Runtime:   go1.8.3
    Arch:      amd64
Client:
    version:   1.0.28-20170815205142+c36e316c3
Service:
    status:    running
    version:   1.0.28-20170815205142+c36e316c3
Desktop app:
    status:    running
    version:   1.0.28-20170815205142+c36e316c3

Let me know if you'd like anymore clarification, also feel free to close this if there's a duplicate. I had a look and couldn't find any but was unsure how to name this and thus how to search for duplicates.

No source file or test is identified. Start with the macOS chat window behavior when loading messages from a deleted user, and determine how the existing deleted-user error is presented; done means the conversation no longer shows an unintended system error.