There is some discussion about a Genshi release over on their mailing list:
There was some activity involving moving the project to GitHub and setting up CI. I found that to be a bit unfortunate because the priority really needs to be on cutting a release.
Moving to Jinja would require a huge amount of work. It has been discussed in the past.
If there is no more development on Genshi, or development is so sporadic that we can't rely on the project, then Trac will eventually need to come up with a plan for moving to another templating engine. I suppose there are alternatives, such as Trac developers contributing to Genshi, but already everyone is quite busy. I also imagine that enough other projects depend on Genshi that someone will eventually fork it, or offer to take over development, like what happened with Babel. Babel moved from Edgewall to the umbrella of the Flask project a few years ago, and seems to have maintainers and a good release cadence now.
On a related topic, I'd really like to see mature Python projects managed by a foundation that could hand off development to new maintainers when a project stalls. I had been thinking about this for a while, and then this post really resonated with my thoughts:
In the Genshi mailing list thread there is a post from a member of the TurboGears project, in which they mention supporting Kajiki as well as Genshi. Kajiki appears to be a fork of Genshi, and it might be possible to migrate to that templating engine. The situation with Genshi and Kajiki was also discussed on a recent Talk Python To Me podcast:
I don't have any experience with Kajiki, but I'd be interested to hear from anyone who does have experience.
Trac should have support for Python 3.3+ starting with release 1.4. Release 1.2 should come out in Q1 2016, and we'll start development towards 1.4 after that. I imagine we might have support for Python 3.3+ on the developer-stable release (1.3.x) by the end of 2016.
Thank you for the positive words about Trac and for contributing to the community :)