Because I’m currently using Threema again, but also use multiple devices, I was very happy when the company announced Threema Web. Threema Web is a webapp which you can run and communicate with your contacts - sounds like the same thing Signal is doing with their Chrome Extension.
But because I’m also a huge fan of Docker, I created a simple Dockerfile to run Threema Web in a container: docker-threema. This image is based on nodejs 7.5. I didn’t use Threema Web very much yet and additional pieces like SaltyRTC and a STUN Server are missing at the moment. But if you just want to try Threema Web and play around, you might find it use full.
Here are the steps to get running:
clone my repository git clone https://github.com/MoriTanosuke/docker-threema.git
change into the cloned directory and build the image docker build -t threema .
run the image docker run --rm -it -p 9966:9966 threema (the container will be removed after you stopped it!)
open your browser at http://localhost:9966/
Here are some screenshots running the Docker container on one of my Windows machines: