I notice that DevMode is not working anymore in mine FF27.
Is this common problem?
According to this post Firefox will not support the plugin from version 27 onward.
So when developing with FF you have to stay on version 24 ESR.
https://groups.google.com/forum/#!topic/google-web-toolkit/QSEjbhhHB4g/discussion
Would be nice to have an official response from the GWT project and Vaadin on this topic.
This isn’t really an official answer, but my take on the issue:
Firefox removed some APIs that are needed by the GWT developer mode plug-in, so there isn’t really any proper solution that the GWT team or Vaadin could implement to resolve this. The APIs were removed as Mozilla sees them as a potential security risk so they are not likely to come back, and also other browsers might remove such APIs in the future. Even if tricks are found so that GWT or Vaadin could apply to get around this, they would most likely have severe drawbacks and a significant performance penalty compared to the current devmode plugin.
Thus, the way forward on these browsers is to use SuperDevMode, which is already a good alternative for devmode in browsers that support source maps and should get better over time both through improvements on the GWT side and through browsers further improving the support for debugging with source maps. The old devmode plugin can be used with older versions of the affected browsers.
Henri, thanks for the clarification