Stop a terrain from been edited

Is there a way to stop a terrain from been edited similar to this inspecter tab is not the active inspector terrain
I am trying to use the height changing brush to merge a smaller terrain with a larger one but it keeps jumping between the small terrain and large one and changing the terrain heights on a terrain I don’t want to effect.
Thx

I don’t think there is. It’s kind of annoying when that happens. The best way I have come up with is keeping everything in source control so you can instantly revert the terrain data you didn’t mean to change. But it still changes it… it would be kinda nice if there was a way to lock all or part of a terrain’s data.