I'm not sure if this is only in my system but these are the steps I take to do it:
1. Open a new document 2. Change the language to HTML 3. Write something simple: "<p>Hello world.</p>" 4. Press Control+Alt+Command+P (This should open the web preview) 5. Now close the web preview with command+w 6. Repeat steps 4 and 5 till it the hang happens.
I went to the Activity monitor to sample the process and this is what I obtained:
https://gist.github.com/jmlopez-rod/5210715
Side Note: I found this weird behavior by trying out the preview on other html documents. It started by not loading anything. I would close it, try again, and then TM would stop working.
-Manuel