Incoming webhook: Bundling messages from same bot

My bot posts multiline messages to Mattermost using an incoming webhook. They work fine, but I would prefer if users could react or reply to each line individually.

When normal users post several messages without interruptions or large delays, they are rendered contiguously under a single user heading, while otherwise behaving like separate posts. This is the behavior I want.

But if my bot posts multiple messages in quick succession, each one gets a full heading with avatar, name, timestamp, and whitespace as if they were unrelated posts, and the resulting look is unusable for me.

Is there any way around this?