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+Title: Missing entity expansion inside PRE
+Author: rodarima
+Created: Sun, 11 Aug 2024 12:48:34 +0000
+State: closed
+
+From https://pubs.opengroup.org/onlinepubs/9699919799/utilities/make.html
+
+The `<pre>` content is rendered:
+
+    .SUFFIXES: .o .c .y .l .a .sh .f .c&#152; .y&#152; .l&#152; .sh&#152; .f&#152;
+
+While the `&#152;` entity must be rendered as `~`, even inside a `pre` block.
+
+Source: https://developer.mozilla.org/en-US/docs/Web/HTML/Element/pre
+
+> If you have to display reserved characters such as <, >, &, and " within the
+> `<pre>` tag, the characters must be escaped using their respective character
+> references.
+> 
+> `<pre>` elements commonly contain `<code>`, `<samp>`, and `<kbd>` elements, to
+> represent computer code, computer output, and user input, respectively.
+
+
+--%--
+From: rodarima
+Date: Sun, 11 Aug 2024 14:23:32 +0000
+
+Dillo reports:
+
+> HTML warning: line 11, Numeric character reference `'&#152;'` is not valid.
+
+Which is handled by `Html_parse_numeric_charref()`:
+
+```c
+if ((codepoint < 0x20 && codepoint != '\t' && codepoint != '\n' &&
+     codepoint != '\f') ||
+    (codepoint >= 0x7f && codepoint <= 0x9f) ||
+    (codepoint >= 0xd800 && codepoint <= 0xdfff) || codepoint > 0x10ffff ||
+    ((codepoint & 0xfffe) == 0xfffe) ||
+    (!(html->DocType == DT_HTML && html->DocTypeVersion >= 5.0f) &&
+     codepoint > 0xffff)) {
+   /* this catches null bytes, errors, codes out of range, disallowed
+    * control chars, permanently undefined chars, and surrogates.
+    */
+   char c = *s;
+   *s = '\0';
+   BUG_MSG("Numeric character reference '&#%s' is not valid.", tok);
+   *s = c;
+
+   codepoint = (codepoint >= 145 && codepoint <= 151) ?
+               Html_ms_stupid_quotes_2ucs(codepoint) : -1;
+}
+```
+
+However the tilde character seems to have the Unicode value U+007e or 126 in
+decimal.
+
+>>> hex(ord('~'))
+'0x7e
+
+Which matches the [ISO-8859-1 character set](https://en.wikipedia.org/wiki/ISO/IEC_8859-1)
+
+From the Wikipedia:
+
+> The popular Windows-1252 character set adds all the missing characters
+> provided by ISO/IEC 8859-15, plus a number of typographic symbols, by
+> replacing the rarely used C1 controls in the range 128 to 159 (hex 80 to 9F).
+> It is very common to mislabel Windows-1252 text as being in ISO-8859-1. A
+> common result was that all the quotes and apostrophes (produced by "smart
+> quotes" in word-processing software) were replaced with question marks or
+> boxes on non-Windows operating systems, making text difficult to read. Many
+> Web browsers and e-mail clients will interpret ISO-8859-1 control codes as
+> Windows-1252 characters, and that behavior was later standardized in
+> HTML5.[20]
+
+
+In the [Windows-1252](https://en.wikipedia.org/wiki/Windows-1252) table I can
+see that the symbol is not the common tilde `~` but a "small tilde" U+02DC `˜`.
+
+So, this seems to be one of those cases where the charset is wrongly set to
+ISO-8859-1 instead of Windows-1252. The document content type seems to be wrong:
+
+```html
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+```
+
+Also, the based on the [HTML 4.01
+spec](https://www.w3.org/TR/html4/charset.html), the numeric entities must refer
+to the "document character set":
+
+> Occasional characters that fall outside this encoding may still be represented
+> by character references. These always refer to the document character set, not
+> the character encoding.
+
+And the character set is *not* the `charset`, but Unicode:
+
+> The ASCII character set is not sufficient for a global information system such
+> as the Web, so HTML uses the much more complete character set called the
+> Universal Character Set (UCS), defined in [ISO10646]. This standard defines a
+> repertoire of thousands of characters used by communities all over the world.
+
+So the entity `&#152;` is pointing to the [Unicode symbol for "Start Of
+String"](https://www.codetable.net/decimal/152), which is non printable.
+
+Therefore, there is no bug on Dillo side, but two bugs on the POSIX manual
+page.
+
+- The entity for small tilde must be `&#x02DC;` or `&#732;`
+- They probably mean ~ not the small tilde.