prometeu-studio/src/main/java/p/studio/controls/shell/StudioRunSurfaceControl.java

@@ -1,5 +1,6 @@
 package p.studio.controls.shell;
 
+import javafx.application.Platform;
 import javafx.beans.binding.Bindings;
 import javafx.beans.property.BooleanProperty;
 import javafx.beans.property.SimpleBooleanProperty;
@@ -12,6 +13,7 @@ import p.studio.Container;
 import p.studio.controls.lifecycle.StudioControlLifecycle;
 import p.studio.controls.lifecycle.StudioControlLifecycleSupport;
 import p.studio.execution.StudioExecutionSessionService;
+import p.studio.execution.StudioExecutionSnapshot;
 import p.studio.execution.StudioExecutionState;
 import p.studio.utilities.events.EventSubscription;
 import p.studio.utilities.i18n.I18n;
@@ -78,7 +80,15 @@ public final class StudioRunSurfaceControl extends HBox implements StudioControl
         if (sessionSubscription != null) {
             return;
         }
-        sessionSubscription = executionSessionService.subscribe(snapshot -> running.set(isRunningState(snapshot.state())));
+        sessionSubscription = executionSessionService.subscribe(this::handleSessionUpdate);
+    }
+
+    private void handleSessionUpdate(final StudioExecutionSnapshot snapshot) {
+        if (Platform.isFxApplicationThread()) {
+            running.set(isRunningState(snapshot.state()));
+            return;
+        }
+        Platform.runLater(() -> running.set(isRunningState(snapshot.state())));
     }
 
     @Override

test-projects/fragments/src/main.pbs

@@ -15,7 +15,7 @@ fn init() -> void
 fn abs_i(v: int) -> int
 {
     if (v < 0) {
-        return 0 - v;
+        return -v;
     }
     return v;
 }