Thanks! I searched this entire blog page for ‘history’ and I only found something to do with map history. That’s why I’m asking here. I gathered from googling that history_graph has been removed, but where should I be looking for what replaced it?
You should read the release notes before updating to see if any breaking changes apply to you. The history graph integration was removed in 0.107 since it was related to the States UI which has now been removed in favor of Lovelace. See here: https://www.home-assistant.io/blog/2020/03/18/release-107/#breaking-changes
The history graph card is the replacement for the integration.