Designer issue in vaadin 14

When i create vaadin 10+ design using eclipse and plugin generates the designer js file instead of the html.

Hello, the design file format was changed in Vaadin 14 from Polymer 2 template to Polymer 3 template. The HTML is embedded in the JS file.

Anssi Tuominen:
Hello, the design file format was changed in Vaadin 14 from Polymer 2 template to Polymer 3 template. The HTML is embedded in the JS file.

Thanks, Anssi Tuominen

Is there any way to convert vaadin 8 designer file to latest one ?

Unfortunately, that is manual work. See the migration documentation about Designer here https://vaadin.com/docs/v14/flow/migration/7-tools-integrations.html#vaadin-designer.