Assertion:
NOTE: Because this element has content between the start and end tags, older browsers may end up displaying the style content it contains. In order to prevent this, it is STRONGLY recommended to embed this information within the SGML/HTML Comment structure (<!-- -->).

Simple script, declaring a variable. SCRIPT body NOT nested in a comment. You should not see the script body ("var a=3"). Browsers not supporting scripting may show the script body:
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Simple script, declaring a variable. SCRIPT body IS nested in a comment. You should not see the script body ("var b=5") :
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