"html_content"the literal text "html_content" (case sensitive) \s*any whitespace character, repeated any number of times
:the literal : (5810 / 728 / 3A16)
\s*any whitespace character, repeated any number of times
"the literal " (3410 / 428 / 2216)
.*?any character (except for line terminators), repeated any number of times
Negative Lookbehind(?<!\\) \\the literal \ (9210 / 1348 / 5C16)
"the literal " (3410 / 428 / 2216)