maxmc and valentin_nasta are both right.
We discovered recently that if Eclipse WTP is installed, the bundled html editor is picked over the Play template editor. It is something we will try to improve.
At the moment, you can force Eclipse to use the Play template editor by selecting Open with ... > Template Editor
from the context menu, or changing the default for *.html
files in Preferences > General > Editors > File Associations
.
For the stack trace, it is a known problem. You have to manually mark the project as a Scala project, using Configure > Add Scala Nature
from the project context menu.