When I run the `tabs` command the file `mix.exs` in the same tab as `NERDTree`, (i.e. tab 2), but I can't access it, as it seems to be in the background or hidden in some way. How can I bring `mix.exs` to the front or even move it to its own tab?

    :tabs                                    
    Tab page 1                               
        myfuncs/funcs_router.ex              
    Tab page 2                               
    >   NERD_tree_2                          
        mix.exs                              
    Tab page 3                               
        myfuncs/docsplug.ex                  
    Press ENTER or type command to continue