This took way longer to figure out that I would have liked, but oh well.

The Goal Setting certain client windows to appear in all tag selections. This is also referred to as “show on all workspaces”.

The Solution I first tried to figure out how to specify that an application class should be associated with multiple tags, but I was never able to do so. I finally found an rc.lua file which contained the information I needed. I put this right after the “layouts” section:

stickyapps =
    -- by class
    ["x-terminal-emulator"] = true
    -- by instance

And this right after the “Check if the application should be floating” section:

    -- Check if the application should be sticky
    if stickyapps[cls] or stickyapps[inst] then
       c.sticky = true

UPDATE: Doh! This doesn’t seem to work for the version of awesome in Debian’s sid. :-(