(one of the Spin authors here.) I'm not all that familiar with the Java ecosystem, but I seem to recall the CheerpJ people having examples for running Swing ap

(one of the Spin authors here.) I'm not all that familiar with the Java ecosystem, but I seem to recall the CheerpJ people having examples for running Swing applications in the browser. (I don't know much about how their solution works, or whether it's open source.) https://cheerpjdemos.leaningtech.com/SwingDemo.html https://cheerpjdemos.leaningtech.com/SwingDemo.html