Title says it all. I am testing out the tab complete on build 481 and none of the commands will work with tab. e.g. /tpa + [tab] results in nothing. However, tab complete works for other plugin commands. Is there like a new setting I am missing?

4c0857f only adds the tab completion framework. The actual individual command tab completion is not yet on the master branch, however I'm awaiting some feedback on #1282 before I can bring in those changes.

This has been fixed in bbe0ca9. You can grab the fix from build 483 on the CI server.