Patch derived from discussion at https://savannah.nongnu.org/bugs/?37503

--- texi2html-5.0/texi2html.pl	2010-06-30 17:01:27.000000000 -0500
+++ texi2html-5.0/texi2html.pl	2014-07-09 01:17:57.062990582 -0500
@@ -2589,7 +2589,12 @@
     my $state = shift;
 
     # FIXME this should be done only once, for @documentencoding
-    my $encoding = lc(Texi2HTML::Config::get_conf('DOCUMENT_ENCODING'));
+    my $encoding;
+    my $input_encoding = Texi2HTML::Config::get_conf('documentencoding');
+    if (defined($input_encoding))
+    {
+      $encoding = lc($input_encoding);
+    }
     if (defined($encoding) and $encoding ne '' and exists($Texi2HTML::Config::t2h_encoding_aliases{$encoding}))
     {
        $encoding = $Texi2HTML::Config::t2h_encoding_aliases{$encoding};

Fix failures in test/encodings.

--- texi2html-5.0/texi2html.pl	2014-07-09 01:22:06.000000000 -0500
+++ texi2html-5.0/texi2html.pl	2014-07-10 23:23:47.182097602 -0500
@@ -53,6 +53,7 @@
 # for translations
 #use encoding 'utf8';
 #use utf8;
+binmode STDERR, ':encoding(utf8)';
 
 #
 # According to
f='/guix/refs/?id=3ecf9d44bb927fc88223a15431428cb741dd1c2c'>refs</a><a class='active' href='/guix/log/po/packages/hu.po'>log</a><a href='/guix/tree/po/packages/hu.po?id=3ecf9d44bb927fc88223a15431428cb741dd1c2c'>tree</a><a href='/guix/commit/po/packages/hu.po?id=3ecf9d44bb927fc88223a15431428cb741dd1c2c'>commit</a><a href='/guix/diff/po/packages/hu.po?id=3ecf9d44bb927fc88223a15431428cb741dd1c2c'>diff</a></td><td class='form'><form class='right' method='get' action='/guix/log/po/packages/hu.po'>
<input type='hidden' name='id' value='3ecf9d44bb927fc88223a15431428cb741dd1c2c'/><select name='qt'>
<option value='grep'>log msg</option>
<option value='author'>author</option>
<option value='committer'>committer</option>
<option value='range'>range</option>
</select>
<input class='txt' type='search' size='10' name='q' value=''/>
<input type='submit' value='search'/>
</form>
</td></tr></table>
<div class='path'>path: <a href='/guix/log/?id=3ecf9d44bb927fc88223a15431428cb741dd1c2c'>root</a>/<a href='/guix/log/po?id=3ecf9d44bb927fc88223a15431428cb741dd1c2c'>po</a>/<a href='/guix/log/po/packages?id=3ecf9d44bb927fc88223a15431428cb741dd1c2c'>packages</a>/<a href='/guix/log/po/packages/hu.po?id=3ecf9d44bb927fc88223a15431428cb741dd1c2c'>hu.po</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/po/packages/hu.po?id=3ecf9d44bb927fc88223a15431428cb741dd1c2c&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2023-05-31 17:23:21 +0200'>2023-05-31</span></td><td><a href='/guix/commit/po/packages/hu.po?id=8e9e6a6482f3ba98d1cdcad344ee488e8751fee7'>nls: Update translations.</a><span class='msg-avail'>...<span class='msg-tooltip'>* doc/guix-cookbook.texi (Top): Mention Slovak.
</span></span></td><td>Florian Pelz</td></tr>
<tr><td><span title='2023-03-07 21:14:57 +0100'>2023-03-07</span></td><td><a href='/guix/commit/po/packages/hu.po?id=d333958763b0840c4cd895601b079b68358a6a46'>nls: Update translations.</a></td><td>Julien Lepiller</td></tr>
<tr><td><span title='2022-12-04 22:25:23 +0100'>2022-12-04</span></td><td><a href='/guix/commit/po/packages/hu.po?id=2e75b328b6bbdadbffe5b643a4891b5026a0defd'>nls: Update translations.</a><span class='msg-avail'>...<span class='msg-tooltip'>po/packages/vi.po: New file.
po/packages/LINGUAS: Add it.
</span></span></td><td>Julien Lepiller</td></tr>
<tr><td><span title='2022-11-04 10:56:38 +0100'>2022-11-04</span></td><td><a href='/guix/commit/po/packages/hu.po?id=a65ce9dd500460af4f97e7398fb35dd817f4c677'>nls: Update translations.</a><span class='msg-avail'>...<span class='msg-tooltip'>* po/guix/lt.po: New file.
* po/guix/LINGUAS: Add lt.
</span></span></td><td>Julien Lepiller</td></tr>
<tr><td><span title='2022-10-06 08:20:20 +0200'>2022-10-06</span></td><td><a href='/guix/commit/po/packages/hu.po?id=70fc8f6d619ce9f16a8cc0bbb10a011bd3a9997a'>nls: Update translations.</a></td><td>Julien Lepiller</td></tr>
<tr><td><span title='2022-09-04 16:52:02 +0200'>2022-09-04</span></td><td><a href='/guix/commit/po/packages/hu.po?id=77e3042aef6d8e519d016555464e466399318b4f'>nls: Update translations.</a></td><td>Julien Lepiller</td></tr>
<tr><td><span title='2022-08-10 23:32:24 +0200'>2022-08-10</span></td><td><a href='/guix/commit/po/packages/hu.po?id=aacbe59fbceb8a93ecb68fed8581dfdd70dafc11'>nls: Update translations.</a><span class='msg-avail'>...<span class='msg-tooltip'>po/guix/bn.po: New file.
po/guix/LINGUAS: Add it.
</span></span></td><td>Julien Lepiller</td></tr>
<tr><td><span title='2022-07-09 21:49:34 +0200'>2022-07-09</span></td><td><a href='/guix/commit/po/packages/hu.po?id=e0d47d8facafb6d6c04741bbf30eefbc68aaefb9'>nls: Update translations.</a><span class='msg-avail'>...<span class='msg-tooltip'>po/guix/tr.po: New file.
po/guix/LINGUAS: Add it.
</span></span></td><td>Julien Lepiller</td></tr>
<tr><td><span title='2022-06-04 17:42:54 +0200'>2022-06-04</span></td><td><a href='/guix/commit/po/packages/hu.po?id=809c57c872a6dd48007d1abf6d7f3dd1482ec53a'>nls: Update translations.</a><span class='msg-avail'>...<span class='msg-tooltip'>po/packages/tr.po: New file.
po/packages/LINGUAS: Add it.
</span></span></td><td>Julien Lepiller</td></tr>
<tr><td><span title='2022-05-01 18:07:34 +0200'>2022-05-01</span></td><td><a href='/guix/commit/po/packages/hu.po?id=6b4124cdcc203d47dc40158062afa1497d73d592'>nls: Update translations.</a><span class='msg-avail'>...<span class='msg-tooltip'>po/guix/ja.po: New file.
po/guix/LINGUAS: Add it.
</span></span></td><td>Julien Lepiller</td></tr>
<tr><td><span title='2022-04-02 18:42:36 +0200'>2022-04-02</span></td><td><a href='/guix/commit/po/packages/hu.po?id=8a208df17fe81fbf34f5a86cc52bb0b8e33c7b96'>nls: Update translations.</a><span class='msg-avail'>...<span class='msg-tooltip'>* po/packages/fi.po: New file.
* po/packages/LINGUAS: Add it.
</span></span></td><td>Julien Lepiller</td></tr>
<tr><td><span title='2022-03-01 22:17:18 +0100'>2022-03-01</span></td><td><a href='/guix/commit/po/packages/hu.po?id=8c92d85e06e65c5cdb5f6c75faf8aa33e5a68513'>nls: Update translations.</a><span class='msg-avail'>...<span class='msg-tooltip'>* po/doc/guix-cookbook.uk.po: New file.
* po/doc/local.mk: Add uk cookbook.
* doc/local.mk: Add uk cookbook.
* po/guix/fa.po: New file.
* po/guix/uk.po: New file.
* po/guix/LINGUAS: Add fa and uk.
</span></span></td><td>Julien Lepiller</td></tr>
<tr><td><span title='2022-02-04 18:29:00 +0100'>2022-02-04</span></td><td><a href='/guix/commit/po/packages/hu.po?id=8391a99d089322a39cbacb1e6dc2979d8b2ef7c9'>nls: Update translations.</a><span class='msg-avail'>...<span class='msg-tooltip'>* po/doc/guix-cookbook.pt_BR.po: New file.
* po/doc/local.mk: Add it.
* doc/local.mk: Add pt_BR cookbook.
</span></span></td><td>Julien Lepiller</td></tr>
<tr><td><span title='2022-01-09 11:35:59 +0100'>2022-01-09</span></td><td><a href='/guix/commit/po/packages/hu.po?id=934b0cdfee2078bad42429427e12d6ee2ddb7fec'>nls: Update translations.</a><span class='msg-avail'>...<span class='msg-tooltip'>* po/doc/guix-cookbook.fi.po: New file.
* po/doc/guix-manual.fi.po: New file.
* po/doc/local.mk: Add them.
* doc/local.mk: Add them.
* po/guix/fi.po: New file.
* po/guix/LINGUAS: Add it.
</span></span></td><td>Julien Lepiller</td></tr>
<tr><td><span title='2021-12-04 19:40:52 +0100'>2021-12-04</span></td><td><a href='/guix/commit/po/packages/hu.po?id=7fcb20a8fa242ab53b9bc97ef0b0367c6a399bd4'>nls: Update translations.</a></td><td>Julien Lepiller</td></tr>