Here is a small, not very in-depth example of how to show and populate a command bar at the bottom of the screen. It could definitely be fleshed out and made into a proper library if there is enough interest. For now, it's just a sample.

The example populates some sample commands. You can modify them as you wish.

You can also set the background and text colors in the css. (Again, perhaps this can be made into an easier-to-use library.) You can even make the background transparent if you want it to be just links.

This could easily be modified (I believe) to have a fixed top bar instead. It's just a question of where the bar gets inserted.