I'm not sure if this is an intentional design choice, but obsidian can be moved by Mechanical Pistons and Bearings. If it is intentional, I'd appreciate a config option to make obsidian immovable. I prefer to preserve the vanilla rule of obsidian being a very difficult material to break and impossible to move

This issue has been marked as stale because it has been inactive for 3 weeks. It will be closed if it remains inactive for another 3 weeks.

This issue has been closed since it has been inactive for 3 weeks since it was marked as stale.

This can already be done! Use a datapack to assign the non_movable tag to obsidian.