What does Ezekiel 35:15 mean?

Just like you celebrated when Israel's land was ruined, I'll do the same to you. Mount Seir, you and all of Edom will be wiped out. Then you'll know that I am the Lord. Ezekiel 35:15 - Modern Text Bible

(Edom's joy over Israel's suffering will come back on them—they'll experience the same devastation, proving God's justice.)