i’m experiencing this problem debugging vaadin 14 app with tomcat 8.5
Caused by: java.lang.IllegalStateException: Running project in development mode with no access to folder '/Users/mstahv/git/tinymce-for-flow/target/checkout'.
Build project in production mode instead, see https://vaadin.com/docs/v14/flow/production/tutorial-production-mode-basic.html
That sure looks like some kind of an issue with the add-on build. Probably something that shouldn’t end up in the add-on jar file is included. Can you create an issue about this to the github project page with short instructions how to reproduce?