diff --git a/bin/i3-companion b/bin/i3-companion
index ed0b678..06caba7 100755
--- a/bin/i3-companion
+++ b/bin/i3-companion
@@ -342,7 +342,7 @@ async def worksplace_exclusive(i3, event):
 
     # Get the window workspace. From an event, w.workspace() is None,
     # so search it in the tree.
-    current_workspace = tree.find_by_id(w.id).workspace()
+    current_workspace = tree.find_by_id(w.id).workspace().num
 
     # Get the list of workspaces with an exclusive app, excluding the
     # current window and windows of the same class.