Hmm... next time it happens I guess.

C-h l is useful if you know what the command is called.  It looks like it is whitespace-something, but i don't see a whitespace-mode.

It was more a nice key combo to know, when I want to check identations in code such as python.

On Sun, Jun 14, 2009 at 8:27 PM, Sivaram Neelakantan <nsivaram.net@gmail.com> wrote:
Rich E <reakinator@gmail.com> writes:

> Hi,
>
> I just accidentally hit some key combination that highlighted all the spaces
> on the left hand side.  This is really useful, but I don't know how I did it
> :)  Anyone know?
>
> thanks,
> Rich

Try M-x view-lossage to see the last few key presses.

 sivaram
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