diff --git a/CHANGES b/CHANGES
index f95a500b2d..fa7b8407e5 100644
--- a/CHANGES
+++ b/CHANGES
@@ -9,6 +9,8 @@ Dependencies
 Incompatible changes
 --------------------
 
+* #9962: texinfo: Customizing styles of emphasized text via ``@definfoenclose``
+  command was not supported because the command was deprecated since texinfo 6.8
 * #2068: :confval:`intersphinx_disabled_reftypes` has changed default value
   from an empty list to ``['std:doc']`` as avoid too surprising silent
   intersphinx resolutions.
@@ -25,6 +27,9 @@ Features added
 Bugs fixed
 ----------
 
+* #9962: texinfo: Deprecation message for ``@definfoenclose`` command on
+  bulding texinfo document
+
 Testing
 --------
 
diff --git a/doc/faq.rst b/doc/faq.rst
index 2e10814395..68eb4745f6 100644
--- a/doc/faq.rst
+++ b/doc/faq.rst
@@ -350,19 +350,3 @@ The following notes may be helpful if you want to create Texinfo files:
   scheme ``info``.  For example::
 
      info:Texinfo#makeinfo_options
-
-- Inline markup
-
-  The standard formatting for ``*strong*`` and ``_emphasis_`` can
-  result in ambiguous output when used to markup parameter names and
-  other values.  Since this is a fairly common practice, the default
-  formatting has been changed so that ``emphasis`` and ``strong`` are
-  now displayed like ```literal'``\s.
-
-  The standard formatting can be re-enabled by adding the following to
-  your :file:`conf.py`::
-
-     texinfo_elements = {'preamble': """
-     @definfoenclose strong,*,*
-     @definfoenclose emph,_,_
-     """}
diff --git a/sphinx/writers/texinfo.py b/sphinx/writers/texinfo.py
index 11f2fba0f9..9881598af4 100644
--- a/sphinx/writers/texinfo.py
+++ b/sphinx/writers/texinfo.py
@@ -58,8 +58,6 @@
 @exampleindent %(exampleindent)s
 @finalout
 %(direntry)s
-@definfoenclose strong,`,'
-@definfoenclose emph,`,'
 @c %%**end of header
 
 @copying
@@ -805,17 +803,21 @@ def depart_line(self, node: Element) -> None:
     # -- Inline
 
     def visit_strong(self, node: Element) -> None:
-        self.body.append('@strong{')
+        self.body.append('`')
 
     def depart_strong(self, node: Element) -> None:
-        self.body.append('}')
+        self.body.append("'")
 
     def visit_emphasis(self, node: Element) -> None:
-        element = 'emph' if not self.in_samp else 'var'
-        self.body.append('@%s{' % element)
+        if self.in_samp:
+            self.body.append('@var{')
+            self.context.append('}')
+        else:
+            self.body.append('`')
+            self.context.append("'")
 
     def depart_emphasis(self, node: Element) -> None:
-        self.body.append('}')
+        self.body.append(self.context.pop())
 
     def is_samp(self, node: Element) -> bool:
         return 'samp' in node['classes']
diff --git a/tests/roots/test-glossary/index.rst b/tests/roots/test-glossary/index.rst
index 88f6ef1b31..1d84a0201c 100644
--- a/tests/roots/test-glossary/index.rst
+++ b/tests/roots/test-glossary/index.rst
@@ -18,5 +18,5 @@ test-glossary
    über
       Gewisse
 
-   änhlich
+   ähnlich
       Dinge
diff --git a/tests/roots/test-root/markup.txt b/tests/roots/test-root/markup.txt
index 2ce542c3e8..41a2fa5831 100644
--- a/tests/roots/test-root/markup.txt
+++ b/tests/roots/test-root/markup.txt
@@ -352,7 +352,7 @@ This tests :CLASS:`role names in uppercase`.
    über
       Gewisse
 
-   änhlich
+   ähnlich
       Dinge
 
 .. productionlist::
diff --git a/tests/test_build_latex.py b/tests/test_build_latex.py
index 19c59dc5e5..aa306bb9e0 100644
--- a/tests/test_build_latex.py
+++ b/tests/test_build_latex.py
@@ -1454,9 +1454,9 @@ def test_latex_glossary(app, status, warning):
     app.builder.build_all()
 
     result = (app.outdir / 'python.tex').read_text()
-    assert (r'\sphinxlineitem{änhlich\index{änhlich@\spxentry{änhlich}|spxpagem}'
+    assert (r'\sphinxlineitem{ähnlich\index{ähnlich@\spxentry{ähnlich}|spxpagem}'
             r'\phantomsection'
-            r'\label{\detokenize{index:term-anhlich}}}' in result)
+            r'\label{\detokenize{index:term-ahnlich}}}' in result)
     assert (r'\sphinxlineitem{boson\index{boson@\spxentry{boson}|spxpagem}\phantomsection'
             r'\label{\detokenize{index:term-boson}}}' in result)
     assert (r'\sphinxlineitem{\sphinxstyleemphasis{fermion}'