`wp_html_split` <script>

[soulseekah]

The following valid HTML post content yields unexpected wp_html_split results:

<script>1 < 4</script>
<p>Welcome</p>

Expected:

array( '', '<script>', '1 < 4', '</script>', '' )

Got:

array( '', '<script>', '1 ', '< 4</script>', '' )

Somewhat related but invalid cases: #39153, #40191

[soulseekah]

tests

[soulseekah]

fix