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JavaScript will hang at the loop starting at line 797 in libs/PageForms.js.

When nextDoubleBracketsEnd are set to -1, and then curIndex = nextDoubleBracketsEnd + 2, i.e., 1, the loop becomes endless.

It seems that the check if ( nextDoubleBracketsEnd < 0 ) should be placed elsewhere, or the whole check for pipes not inside double square brackets rewritten.