diff --git a/scalafmt-core/shared/src/main/scala/org/scalafmt/internal/Router.scala b/scalafmt-core/shared/src/main/scala/org/scalafmt/internal/Router.scala
index d11e17e2c9..a0e1fc24f4 100644
--- a/scalafmt-core/shared/src/main/scala/org/scalafmt/internal/Router.scala
+++ b/scalafmt-core/shared/src/main/scala/org/scalafmt/internal/Router.scala
@@ -702,7 +702,9 @@ class Router(formatOps: FormatOps) {
             case Newlines.unfold =>
               val rightParent = rightOwner.parent.get
               val slbEnd =
-                if (defn) beforeDefRhs.fold(getLastToken(rightParent))(_.left)
+                if (defn)
+                  beforeDefRhs
+                    .fold(getLastToken(rightParent))(prevNonComment(_).left)
                 else getLastToken(getLastCall(rightParent))
               val multipleArgs = isSeqMulti(getArgs(next(ft).meta.leftOwner))
               val nft = tokens.tokenAfter(close)
diff --git a/scalafmt-tests/src/test/resources/scala3/OptionalBraces_unfold.stat b/scalafmt-tests/src/test/resources/scala3/OptionalBraces_unfold.stat
index 5a8e49bd97..26d2bccbe3 100644
--- a/scalafmt-tests/src/test/resources/scala3/OptionalBraces_unfold.stat
+++ b/scalafmt-tests/src/test/resources/scala3/OptionalBraces_unfold.stat
@@ -4741,8 +4741,7 @@ extension (s: String)
   def foo(): Unit = ???
   def bar(): Unit = ???
 >>>
-extension
-  (s: String)
+extension(s: String)
    /** ... */
    def foo(): Unit = ???
    def bar(): Unit = ???