We use Lighthouse as issue tracker at:
Bug reports are incredibly helpful, so take time to report bugs and request features in our ticket tracker. We’re always grateful for patches to Play’s code. Indeed, bug reports with attached patches will get fixed far quickly than those without any.
Please include as much relevant information as possible including the exact framework version you’re using and a code snippet that reproduces the problem.
Don’t have too much expectations. Unless the bug is really a serious “everything is broken” thing, you’re creating a ticket to start a discussion. Having a patch (or a branch on Github we can pull from) is better, but then again we’ll only pull high quality branches that make sense to be in the core of Play.