A Slack Post quickbuild step has two icon options. I can't seem to be able to use the "Icon URL" option. It is always overridden by the "Icon Emoji" and I can't seem to set the Icon Emoji to none. When I delete it in the step, it re-fills in with "${current.getDefaultEmoji()}" once saved.
How does one use the URL option, or more specifically, how do you prevent the Icon Emoji step settings from auto-populating with an icon I don't wish to use?