Broken profile icons for bots without using gravatar

[wurst-hans]

Due to privacy, we have disabled Gravatar on our self-hosted Zulip installation. Using Zulip in webbrowser the Welcome Bot is displayed using a fallback image like

But on mobile (Android app V 27.191) the image for the Welcome Bot is totally broken

Is there any way to fix this on side of server, i.e. is there a way to set a custom profile image for the Welcome Bot?

[gnprice]

Thanks @wurst-hans for the report!

Chat thread here, with some debugging: https://chat.zulip.org/#narrow/stream/48-mobile/topic/Broken.20profile.20icons.20for.20bots.20without.20using.20gravatar.20.23M5502/near/1441438