Is it possible to have a buffer showing the headers of a file in a
buffer in a popup window to the left of the main window in org-mode
please?

We already have 'neotree' but that just shows the files in a directory.
What I'm looking for is something like 'Imenu' but in a popup buffer,
which is activated in something like 'M-F8' and displays, and then when
'M-F8' is used again it closes the popup. From the popup you can move
about the headings in your file with ease just using the keyboard, and
without having to use a mouse.

Ideally, this could be used for any buffer that is being used, whether
its latex, mediawiki, or whatever, although possibly not for gnus.

So can it be done please?

Thanks
Sharon.
-- 
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