Thanks, I think it helps as the default `mode-line-buffer-id` face of the
active buffer is overridden, and it becomes the "inactive face". I think it
solves this problem, but maybe a custom face in the mode-line faces group
itself would be more accessible.

Another workaround I found was to use the `inverse-video` face option in
the `mode-line-inactive` face. It doesn't give me too much freedom to
customize the face.

On Sat, Jan 29, 2022 at 9:25 PM Drew Adams <drew.adams@oracle.com> wrote:

> > Mode-line has face options for when it's
> > active and inactive but `mode-line-buffer-id`
> > just allows customization on the active form,
> > please consider adding the option to allow
> > customizing the face of the `mode-line-buffer-id`
> > when the mode-line is inactive too.
>
> See library `modeline-win.el'.
> Does it do what you're looking for?
>
> It highlights the buffer name in the
> mode-line for the selected window.
>
> That is, whichever window is currently
> selected, its buffer name in the mode
> line is highlighted (using face
> `mlw-mode-line-buffer-id-selected-window').
>
> The code is here:
>
> https://www.emacswiki.org/emacs/download/modeline-win.el
>
> It's just a few lines of code.
>