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                  
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