Small window width causes crash

[CSpencerND]

If I make the window width really narrow nvim crashes. Admittedly, I don't see why I would ever shrink the window to such a small width but I don't think it should cause a crash. I tried my best to clean up the error message.

E5108: Error executing lua .../pack/packer/start/bufferline.nvim/lua/bufferline/ui.lua:560:
    bad argument #1 to 'pairs' (table expected, got string)   
stack traceback:         
    [C]: in function 'pairs'                  
        .../pack/packer/start/bufferline.nvim/lua/bufferline/ui.lua:560: in function 'extend_highlight'                      
        .../pack/packer/start/bufferline.nvim/lua/bufferline/ui.lua:589: in function 'to_tabline_str'                        
        .../pack/packer/start/bufferline.nvim/lua/bufferline/ui.lua:669: in function 'join'         
        .../pack/packer/start/bufferline.nvim/lua/bufferline/ui.lua:716: in function 'tabline'      
        ...ite/pack/packer/start/bufferline.nvim/lua/bufferline.lua:106: in function 
        <...ite/pack/packer/start/bufferline.nvim/lua/bufferline.lua:97>