Changes in LitElement are not displayed on startup

I’m developing a Vaadin addon with the ‘vaadin/npm-addon-template’. Similiar to the clock-example I’ve added classes for my own component. When I start the application with mvn jetty:run and navigate to my component View-Route /map the component will be displayed. I did some modifications inside my leaflet-kml.ts file and restarted the application however the changes will not be displayed in the browser. There is no error message. The source code of this simple component is publicly available at: https://github.com/jhoffmann99/vaadin-leaflet-kml Can somebody give me a hint what’s wrong with it? thanks in advance, Jürgen

Did you rebuild the addon?

I also executed mvn clean install

When I execute mvn vaadin:build-frontend I get an error:

[ERROR] Error: [vite]: Rollup failed to resolve import "@vaadin/vaadin-themable-mixin" from "target/frontend/generated-flow-imports-fallback.js".
[ERROR] This is most likely unintended because it can break your application at runtime.
[ERROR] If you do want to externalize this module explicitly add it to
[ERROR] `build.rollupOptions.external`
[ERROR]     at onRollupWarning (file:///C:/Users/juergen/IdeaProjects/jhoffmann-leaflet/node_modules/.pnpm/vite@3.1.0/node_modules/vite/dist/node/chunks/dep-665b0112.js:45824:19)
[ERROR]     at onwarn (file:///C:/Users/juergen/IdeaProjects/jhoffmann-leaflet/node_modules/.pnpm/vite@3.1.0/node_modules/vite/dist/node/chunks/dep-665b0112.js:45622:13)
[ERROR]     at Object.onwarn (file:///C:/Users/juergen/IdeaProjects/jhoffmann-leaflet/node_modules/.pnpm/rollup@2.78.1/node_modules/rollup/dist/es/shared/rollup.js:23225:13)
[ERROR]     at ModuleLoader.handleResolveId (file:///C:/Users/juergen/IdeaProjects/jhoffmann-leaflet/node_modules/.pnpm/rollup@2.78.1/node_modules/rollup/dist/es/shared/rollup.js:22352:26)
[ERROR]     at file:///C:/Users/juergen/IdeaProjects/jhoffmann-leaflet/node_modules/.pnpm/rollup@2.78.1/node_modules/rollup/dist/es/shared/rollup.js:22313:26

I also get this error when I delete my component and trigger the frontend build for the clock example component

You could try the latest 23.3.x to see if the vite upgrade in between those version helps with this error. The workflow to create add-ons is kinda clumsy, because flow needs to pick them up via maven. Personally I would develop add-ons in my main project and once they are “finished” I would extract them to a separate repo, versioning it and add it to my application. Changing the addon afterwards, requires a new version, which normally forces maven to access the newly version instead of relying on snapshot resolution.

How can I try the latest 23.3.x version? just executing npm update?

You have to update your pom