Being that Ubuntu has a larger user base than nearly any other distro and failure of HUD being less than graceful:
0. Previously Chromium or any other HUD capable application is running
1. Sublime window is active
2. Activate HUD with <ALT>
3. See 0's (Chromium in this example) menu items.
I believe such a fix would be trivial. HUD simply relies on Global Menus.
Overall great product. I'm happy with it. I'd ordinarily hack something together for this and shoot over a pull request, but I guess I'll just have to offer a license as a bounty.