This does it slowly and is one character shorter than the one you gave in your spoiler:

<Reveal this spoiler or all spoilers in this node or all in this thread>

Update: Btw one could try this (CAUTION! DON'T TYPE BLINDLY!):

<Reveal this spoiler>
but it doesn't work, because
<Reveal this spoiler>

Update: On the other hand, this works, and is shorter than the first one:

<Reveal this spoiler>

Update: the following works too and is even shorter:

<Reveal this spoiler>

Update: and one more character shorter is:

<Reveal this spoiler>

Update: the following has the same length as the first one in this node, but is a slower than that:

<Reveal this spoiler>

In reply to Re: Guess what it does ... and a challenge by ambrus
in thread Guess what it does ... and a challenge by liverpole

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