here's 56. I used a period since the other char acted funky in my editor.

edit: trimmed two chars, removed unneccessary character replacements. 
#2345678 1 2345678 2 2345678 3 2345678 4 2345678 5 23456
s/<!--(.*?)-->/(my$x=$1)=~s!-(-?)!$1.!g;"<!--$x-->"/egs;

[download]

two chars less, 54: 
#2345678 1 2345678 2 2345678 3 2345678 4 2345678 5 23456
s/<!--(.*?)-->/($_=$1)=~s!-(-?)!$1.!g;"<!--$_-->"/egs;

[download]

makes less changes, but adds to 55: 
#2345678 1 2345678 2 2345678 3 2345678 4 2345678 5 23456
s/<!--(.*?)-->/($_=$1)=~s!-(-+?)!$1.!g;"<!--$_-->"/egs;

[download]

In reply to Re: Golf: Fix de facto HTML comments by bageler
in thread Golf: Fix de facto HTML comments by tye

Title:
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