diff --git a/.git-blame-ignore-revs b/.git-blame-ignore-revs
index 6ebecf67..385b6754 100644
--- a/.git-blame-ignore-revs
+++ b/.git-blame-ignore-revs
@@ -4,3 +4,6 @@ b049841d5707d5bd87be516d8cda7be2a7585eae
 # Reformatted test code
 e437d63c40713e0645a4895bbe5a0fc565cd56db
 
+
+# Scala Steward: Reformat with scalafmt 3.8.6
+7a65773fa5c7d3bf0fe192375a2eaceacde274e8
diff --git a/.scalafmt.conf b/.scalafmt.conf
index aa39efda..bc3d7e3a 100644
--- a/.scalafmt.conf
+++ b/.scalafmt.conf
@@ -1,4 +1,4 @@
-version = "3.8.3"
+version = "3.8.6"
 
 align.preset = none
 align.openParenCallSite = false
diff --git a/build.mill b/build.mill
index 999f996c..f342f8ca 100644
--- a/build.mill
+++ b/build.mill
@@ -184,7 +184,7 @@ object os extends Module {
       object testJarWriter extends JavaModule
       object testJarReader extends JavaModule
       object testJarExit extends JavaModule
-      object testSpawnExitHook extends ScalaModule{
+      object testSpawnExitHook extends ScalaModule {
         def scalaVersion = OsJvmModule.this.scalaVersion()
         def moduleDeps = Seq(OsJvmModule.this)
       }
diff --git a/os/src/FileOps.scala b/os/src/FileOps.scala
index c0ee81ea..efc397f3 100644
--- a/os/src/FileOps.scala
+++ b/os/src/FileOps.scala
@@ -339,11 +339,15 @@ object remove extends Function1[Path, Boolean] {
         if (Files.isDirectory(nioTarget, LinkOption.NOFOLLOW_LINKS)) {
           for (p <- walk.stream(target, preOrder = false)) {
             try remove(p)
-            catch { case e: Throwable if ignoreErrors => /*ignore*/ }
+            catch {
+              case e: Throwable if ignoreErrors => /*ignore*/
+            }
           }
         }
         try Files.delete(nioTarget)
-        catch { case e: Throwable if ignoreErrors => /*ignore*/ }
+        catch {
+          case e: Throwable if ignoreErrors => /*ignore*/
+        }
       }
     }
   }
diff --git a/os/src/ProcessOps.scala b/os/src/ProcessOps.scala
index 6175e87c..7ca90ba5 100644
--- a/os/src/ProcessOps.scala
+++ b/os/src/ProcessOps.scala
@@ -332,7 +332,9 @@ case class proc(command: Shellable*) {
         override def run(): Unit = {
           while (proc.wrapped.isAlive) Thread.sleep(1)
           try Runtime.getRuntime().removeShutdownHook(t)
-          catch { case e: Throwable => /*do nothing*/ }
+          catch {
+            case e: Throwable => /*do nothing*/
+          }
         }
       }
     )
diff --git a/os/watch/src/FSEventsWatcher.scala b/os/watch/src/FSEventsWatcher.scala
index d41b092e..afa334b1 100644
--- a/os/watch/src/FSEventsWatcher.scala
+++ b/os/watch/src/FSEventsWatcher.scala
@@ -32,7 +32,9 @@ class FSEventsWatcher(
         else {
           existingFolders.add(p)
           try os.walk.stream(p).foreach(nestedPaths.append(_))
-          catch { case e: Throwable => /*do nothing*/ }
+          catch {
+            case e: Throwable => /*do nothing*/
+          }
         }
       }
       onEvent((paths ++ nestedPaths).toSet)