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<h1>The iframe sandbox attribute</h1>
<iframe src="https://horje.com" sandbox="allow-forms">
<p>Your browser does not support iframes.</p>
</iframe>
<p>The "Submit" button will submit the form in the inline frame.</p>
<p>Since the sandbox attribute is set to an empty string (""), the submission of the form in the inline frame will be blocked.</p>
<p>Add "allow-forms" to the sandbox attribute, to allow form submission.</p>
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