diff --git a/CHANGES b/CHANGES
index 5637f66d6..600efc466 100644
--- a/CHANGES
+++ b/CHANGES
@@ -12,6 +12,8 @@ Deprecated
 
 * ``sphinx.builders.latex.LaTeXBuilder.usepackages``
 * ``sphinx.builders.latex.LaTeXBuilder.usepackages_afger_hyperref``
+* ``sphinx.ext.autodoc.SingledispatchFunctionDocumenter``
+* ``sphinx.ext.autodoc.SingledispatchMethodDocumenter``
 
 Features added
 --------------
@@ -22,11 +24,14 @@ Features added
   nested declarations.
 * #8081: LaTeX: Allow to add LaTeX package via ``app.add_latex_package()`` until
   just before writing .tex file
+* #7996: manpage: Add :confval:`man_make_section_directory` to make a section
+  directory on build man page
 
 Bugs fixed
 ----------
 
 * #8085: i18n: Add support for having single text domain
+* #6640: i18n: Failed to override system message translation
 * #8143: autodoc: AttributeError is raised when False value is passed to
   autodoc_default_options
 * #8103: autodoc: functools.cached_property is not considered as a property
@@ -34,15 +39,22 @@ Bugs fixed
   by string not ending with blank lines
 * #8142: autodoc: Wrong constructor signature for the class derived from
   typing.Generic
+* #8157: autodoc: TypeError is raised when annotation has invalid __args__
+* #7964: autodoc: Tuple in default value is wrongly rendered
 * #8200: autodoc: type aliases break type formatting of autoattribute
 * #8192: napoleon: description is disappeared when it contains inline literals
 * #8142: napoleon: Potential of regex denial of service in google style docs
 * #8169: LaTeX: pxjahyper loaded even when latex_engine is not platex
 * #8175: intersphinx: Potential of regex denial of service by broken inventory
+* #8277: sphinx-build: missing and redundant spacing (and etc) for console
+  output on building
+* #7973: imgconverter: Check availability of imagemagick many times
 * #8093: The highlight warning has wrong location in some builders (LaTeX,
   singlehtml and so on)
 * #8239: Failed to refer a token in productionlist if it is indented
 * #8268: linkcheck: Report HTTP errors when ``linkcheck_anchors`` is ``True``
+* #8245: linkcheck: take source directory into account for local files
+* #6914: figure numbers are unexpectedly assigned to uncaptioned items
 
 Testing
 --------
diff --git a/doc/extdev/deprecated.rst b/doc/extdev/deprecated.rst
index d7ad21fff..2bb8aebfd 100644
--- a/doc/extdev/deprecated.rst
+++ b/doc/extdev/deprecated.rst
@@ -36,6 +36,16 @@ The following is a list of deprecated interfaces.
      - 5.0
      - N/A
 
+   * - ``sphinx.ext.autodoc.SingledispatchFunctionDocumenter``
+     - 3.3
+     - 5.0
+     - ``sphinx.ext.autodoc.FunctionDocumenter``
+
+   * - ``sphinx.ext.autodoc.SingledispatchMethodDocumenter``
+     - 3.3
+     - 5.0
+     - ``sphinx.ext.autodoc.MethodDocumenter``
+
    * - ``sphinx.ext.autodoc.members_set_option()``
      - 3.2
      - 5.0
diff --git a/doc/usage/configuration.rst b/doc/usage/configuration.rst
index 3fc3a5306..270fcbf33 100644
--- a/doc/usage/configuration.rst
+++ b/doc/usage/configuration.rst
@@ -2245,6 +2245,12 @@ These options influence manual page output.
 
    .. versionadded:: 1.1
 
+.. confval:: man_make_section_directory
+
+   If true, make a section directory on build man page.  Default is False.
+
+   .. versionadded:: 3.3
+
 
 .. _texinfo-options:
 
diff --git a/sphinx/application.py b/sphinx/application.py
index 385b74d8a..f91027bf7 100644
--- a/sphinx/application.py
+++ b/sphinx/application.py
@@ -18,7 +18,7 @@ import warnings
 from collections import deque
 from io import StringIO
 from os import path
-from typing import Any, Callable, Dict, IO, List, Tuple, Union
+from typing import Any, Callable, Dict, IO, List, Optional, Tuple, Union
 
 from docutils import nodes
 from docutils.nodes import Element, TextElement
@@ -293,7 +293,10 @@ class Sphinx:
                 if catalog.domain == 'sphinx' and catalog.is_outdated():
                     catalog.write_mo(self.config.language)
 
-            locale_dirs = [None, path.join(package_dir, 'locale')] + list(repo.locale_dirs)
+            locale_dirs = [None]  # type: List[Optional[str]]
+            locale_dirs += list(repo.locale_dirs)
+            locale_dirs += [path.join(package_dir, 'locale')]
+
             self.translator, has_translation = locale.init(locale_dirs, self.config.language)
             if has_translation or self.config.language == 'en':
                 # "en" never needs to be translated
diff --git a/sphinx/builders/html/__init__.py b/sphinx/builders/html/__init__.py
index c30aa9cfd..beb650991 100644
--- a/sphinx/builders/html/__init__.py
+++ b/sphinx/builders/html/__init__.py
@@ -641,17 +641,17 @@ class StandaloneHTMLBuilder(Builder):
     def gen_additional_pages(self) -> None:
         # additional pages from conf.py
         for pagename, template in self.config.html_additional_pages.items():
-            logger.info(' ' + pagename, nonl=True)
+            logger.info(pagename + ' ', nonl=True)
             self.handle_page(pagename, {}, template)
 
         # the search page
         if self.search:
-            logger.info(' search', nonl=True)
+            logger.info('search ', nonl=True)
             self.handle_page('search', {}, 'search.html')
 
         # the opensearch xml file
         if self.config.html_use_opensearch and self.search:
-            logger.info(' opensearch', nonl=True)
+            logger.info('opensearch ', nonl=True)
             fn = path.join(self.outdir, '_static', 'opensearch.xml')
             self.handle_page('opensearch', {}, 'opensearch.xml', outfilename=fn)
 
@@ -669,7 +669,7 @@ class StandaloneHTMLBuilder(Builder):
             'genindexcounts': indexcounts,
             'split_index': self.config.html_split_index,
         }
-        logger.info(' genindex', nonl=True)
+        logger.info('genindex ', nonl=True)
 
         if self.config.html_split_index:
             self.handle_page('genindex', genindexcontext,
@@ -691,7 +691,7 @@ class StandaloneHTMLBuilder(Builder):
                 'content': content,
                 'collapse_index': collapse,
             }
-            logger.info(' ' + indexname, nonl=True)
+            logger.info(indexname + ' ', nonl=True)
             self.handle_page(indexname, indexcontext, 'domainindex.html')
 
     def copy_image_files(self) -> None:
@@ -785,7 +785,7 @@ class StandaloneHTMLBuilder(Builder):
 
     def copy_static_files(self) -> None:
         try:
-            with progress_message(__('copying static files... ')):
+            with progress_message(__('copying static files')):
                 ensuredir(path.join(self.outdir, '_static'))
 
                 # prepare context for templates
diff --git a/sphinx/builders/linkcheck.py b/sphinx/builders/linkcheck.py
index 1083e82ec..a9e6b05b0 100644
--- a/sphinx/builders/linkcheck.py
+++ b/sphinx/builders/linkcheck.py
@@ -211,7 +211,7 @@ class CheckExternalLinksBuilder(Builder):
                 else:
                     return 'redirected', new_url, 0
 
-        def check() -> Tuple[str, str, int]:
+        def check(docname: str) -> Tuple[str, str, int]:
             # check for various conditions without bothering the network
             if len(uri) == 0 or uri.startswith(('#', 'mailto:')):
                 return 'unchecked', '', 0
@@ -220,7 +220,8 @@ class CheckExternalLinksBuilder(Builder):
                     # non supported URI schemes (ex. ftp)
                     return 'unchecked', '', 0
                 else:
-                    if path.exists(path.join(self.srcdir, uri)):
+                    srcdir = path.dirname(self.env.doc2path(docname))
+                    if path.exists(path.join(srcdir, uri)):
                         return 'working', '', 0
                     else:
                         for rex in self.to_ignore:
@@ -257,7 +258,7 @@ class CheckExternalLinksBuilder(Builder):
             uri, docname, lineno = self.wqueue.get()
             if uri is None:
                 break
-            status, info, code = check()
+            status, info, code = check(docname)
             self.rqueue.put((uri, docname, lineno, status, info, code))
 
     def process_result(self, result: Tuple[str, str, int, str, str, int]) -> None:
diff --git a/sphinx/builders/manpage.py b/sphinx/builders/manpage.py
index 4166dece9..2a10ba62f 100644
--- a/sphinx/builders/manpage.py
+++ b/sphinx/builders/manpage.py
@@ -24,7 +24,7 @@ from sphinx.util import logging
 from sphinx.util import progress_message
 from sphinx.util.console import darkgreen  # type: ignore
 from sphinx.util.nodes import inline_all_toctrees
-from sphinx.util.osutil import make_filename_from_project
+from sphinx.util.osutil import ensuredir, make_filename_from_project
 from sphinx.writers.manpage import ManualPageWriter, ManualPageTranslator
 
 
@@ -80,7 +80,12 @@ class ManualPageBuilder(Builder):
             docsettings.authors = authors
             docsettings.section = section
 
-            targetname = '%s.%s' % (name, section)
+            if self.config.man_make_section_directory:
+                ensuredir(path.join(self.outdir, str(section)))
+                targetname = '%s/%s.%s' % (section, name, section)
+            else:
+                targetname = '%s.%s' % (name, section)
+
             logger.info(darkgreen(targetname) + ' { ', nonl=True)
             destination = FileOutput(
                 destination_path=path.join(self.outdir, targetname),
@@ -115,6 +120,7 @@ def setup(app: Sphinx) -> Dict[str, Any]:
 
     app.add_config_value('man_pages', default_man_pages, None)
     app.add_config_value('man_show_urls', False, None)
+    app.add_config_value('man_make_section_directory', False, None)
 
     return {
         'version': 'builtin',
diff --git a/sphinx/environment/collectors/toctree.py b/sphinx/environment/collectors/toctree.py
index e168bd9c4..d6cdc8354 100644
--- a/sphinx/environment/collectors/toctree.py
+++ b/sphinx/environment/collectors/toctree.py
@@ -224,6 +224,10 @@ class TocTreeCollector(EnvironmentCollector):
         def get_figtype(node: Node) -> str:
             for domain in env.domains.values():
                 figtype = domain.get_enumerable_node_type(node)
+                if domain.name == 'std' and not domain.get_numfig_title(node):  # type: ignore
+                    # Skip if uncaptioned node
+                    continue
+
                 if figtype:
                     return figtype
 
diff --git a/sphinx/ext/autodoc/__init__.py b/sphinx/ext/autodoc/__init__.py
index 83c44c8df..434fc40e9 100644
--- a/sphinx/ext/autodoc/__init__.py
+++ b/sphinx/ext/autodoc/__init__.py
@@ -1302,6 +1302,11 @@ class SingledispatchFunctionDocumenter(FunctionDocumenter):
     Retained for backwards compatibility, now does the same as the FunctionDocumenter
     """
 
+    def __init__(self, *args: Any, **kwargs: Any) -> None:
+        warnings.warn("%s is deprecated." % self.__class__.__name__,
+                      RemovedInSphinx50Warning, stacklevel=2)
+        super().__init__(*args, **kwargs)
+
 
 class DecoratorDocumenter(FunctionDocumenter):
     """
@@ -1938,6 +1943,11 @@ class SingledispatchMethodDocumenter(MethodDocumenter):
     Retained for backwards compatibility, now does the same as the MethodDocumenter
     """
 
+    def __init__(self, *args: Any, **kwargs: Any) -> None:
+        warnings.warn("%s is deprecated." % self.__class__.__name__,
+                      RemovedInSphinx50Warning, stacklevel=2)
+        super().__init__(*args, **kwargs)
+
 
 class AttributeDocumenter(DocstringStripSignatureMixin, ClassLevelDocumenter):  # type: ignore
     """
diff --git a/sphinx/locale/__init__.py b/sphinx/locale/__init__.py
index 385ca3566..5210dc725 100644
--- a/sphinx/locale/__init__.py
+++ b/sphinx/locale/__init__.py
@@ -106,7 +106,7 @@ class _TranslationProxy(UserString):
 translators = defaultdict(NullTranslations)  # type: Dict[Tuple[str, str], NullTranslations]
 
 
-def init(locale_dirs: List[str], language: str,
+def init(locale_dirs: List[Optional[str]], language: str,
          catalog: str = 'sphinx', namespace: str = 'general') -> Tuple[NullTranslations, bool]:
     """Look for message catalogs in `locale_dirs` and *ensure* that there is at
     least a NullTranslations catalog set in `translators`. If called multiple
diff --git a/sphinx/pycode/ast.py b/sphinx/pycode/ast.py
index 9bafff11c..2583448d5 100644
--- a/sphinx/pycode/ast.py
+++ b/sphinx/pycode/ast.py
@@ -166,14 +166,28 @@ class _UnparseVisitor(ast.NodeVisitor):
         return "{" + ", ".join(self.visit(e) for e in node.elts) + "}"
 
     def visit_Subscript(self, node: ast.Subscript) -> str:
-        return "%s[%s]" % (self.visit(node.value), self.visit(node.slice))
+        def is_simple_tuple(value: ast.AST) -> bool:
+            return (
+                isinstance(value, ast.Tuple) and
+                bool(value.elts) and
+                not any(isinstance(elt, ast.Starred) for elt in value.elts)
+            )
+
+        if is_simple_tuple(node.slice):
+            elts = ", ".join(self.visit(e) for e in node.slice.elts)  # type: ignore
+            return "%s[%s]" % (self.visit(node.value), elts)
+        elif isinstance(node.slice, ast.Index) and is_simple_tuple(node.slice.value):
+            elts = ", ".join(self.visit(e) for e in node.slice.value.elts)  # type: ignore
+            return "%s[%s]" % (self.visit(node.value), elts)
+        else:
+            return "%s[%s]" % (self.visit(node.value), self.visit(node.slice))
 
     def visit_UnaryOp(self, node: ast.UnaryOp) -> str:
         return "%s %s" % (self.visit(node.op), self.visit(node.operand))
 
     def visit_Tuple(self, node: ast.Tuple) -> str:
         if node.elts:
-            return ", ".join(self.visit(e) for e in node.elts)
+            return "(" + ", ".join(self.visit(e) for e in node.elts) + ")"
         else:
             return "()"
 
diff --git a/sphinx/transforms/post_transforms/images.py b/sphinx/transforms/post_transforms/images.py
index f2cacac3c..949c09dde 100644
--- a/sphinx/transforms/post_transforms/images.py
+++ b/sphinx/transforms/post_transforms/images.py
@@ -11,7 +11,7 @@
 import os
 import re
 from math import ceil
-from typing import Any, Dict, List, Tuple
+from typing import Any, Dict, List, Optional, Tuple
 
 from docutils import nodes
 
@@ -175,6 +175,13 @@ class ImageConverter(BaseImageConverter):
     """
     default_priority = 200
 
+    #: The converter is available or not.  Will be filled at the first call of
+    #: the build.  The result is shared in the same process.
+    #:
+    #: .. todo:: This should be refactored not to store the state without class
+    #:           variable.
+    available = None  # type: Optional[bool]
+
     #: A conversion rules the image converter supports.
     #: It is represented as a list of pair of source image format (mimetype) and
     #: destination one::
@@ -187,16 +194,14 @@ class ImageConverter(BaseImageConverter):
     conversion_rules = []  # type: List[Tuple[str, str]]
 
     def __init__(self, *args: Any, **kwargs: Any) -> None:
-        self.available = None   # type: bool
-                                # the converter is available or not.
-                                # Will be checked at first conversion
         super().__init__(*args, **kwargs)
 
     def match(self, node: nodes.image) -> bool:
         if not self.app.builder.supported_image_types:
             return False
         elif self.available is None:
-            self.available = self.is_available()
+            # store the value to the class variable to share it during the build
+            self.__class__.available = self.is_available()
 
         if not self.available:
             return False
diff --git a/sphinx/util/typing.py b/sphinx/util/typing.py
index 4dac3b695..8eca67220 100644
--- a/sphinx/util/typing.py
+++ b/sphinx/util/typing.py
@@ -109,7 +109,10 @@ def _stringify_py37(annotation: Any) -> str:
         return repr(annotation)
 
     if getattr(annotation, '__args__', None):
-        if qualname == 'Union':
+        if not isinstance(annotation.__args__, (list, tuple)):
+            # broken __args__ found
+            pass
+        elif qualname == 'Union':
             if len(annotation.__args__) > 1 and annotation.__args__[-1] is NoneType:
                 if len(annotation.__args__) > 2:
                     args = ', '.join(stringify(a) for a in annotation.__args__[:-1])
diff --git a/tests/test_build_manpage.py b/tests/test_build_manpage.py
index c3c41a2ae..d4b1a320e 100644
--- a/tests/test_build_manpage.py
+++ b/tests/test_build_manpage.py
@@ -30,6 +30,13 @@ def test_all(app, status, warning):
     assert 'Footnotes' not in content
 
 
+@pytest.mark.sphinx('man', testroot='basic',
+                    confoverrides={'man_make_section_directory': True})
+def test_man_make_section_directory(app, status, warning):
+    app.build()
+    assert (app.outdir / '1' / 'python.1').exists()
+
+
 @pytest.mark.sphinx('man', testroot='directive-code')
 def test_captioned_code_block(app, status, warning):
     app.builder.build_all()
diff --git a/tests/test_intl.py b/tests/test_intl.py
index 1d1282baa..c0b87d5ce 100644
--- a/tests/test_intl.py
+++ b/tests/test_intl.py
@@ -14,8 +14,10 @@ import re
 
 import pytest
 from babel.messages import pofile, mofile
+from babel.messages.catalog import Catalog
 from docutils import nodes
 
+from sphinx import locale
 from sphinx.testing.util import (
     path, etree_parse, strip_escseq,
     assert_re_search, assert_not_re_search, assert_startswith, assert_node
@@ -1289,3 +1291,30 @@ def test_image_glob_intl_using_figure_language_filename(app):
 
 def getwarning(warnings):
     return strip_escseq(warnings.getvalue().replace(os.sep, '/'))
+
+
+@pytest.mark.sphinx('html', testroot='basic', confoverrides={'language': 'de'})
+def test_customize_system_message(make_app, app_params, sphinx_test_tempdir):
+    try:
+        # clear translators cache
+        locale.translators.clear()
+
+        # prepare message catalog (.po)
+        locale_dir = sphinx_test_tempdir / 'basic' / 'locales' / 'de' / 'LC_MESSAGES'
+        locale_dir.makedirs()
+        with (locale_dir / 'sphinx.po').open('wb') as f:
+            catalog = Catalog()
+            catalog.add('Quick search', 'QUICK SEARCH')
+            pofile.write_po(f, catalog)
+
+        # construct application and convert po file to .mo
+        args, kwargs = app_params
+        app = make_app(*args, **kwargs)
+        assert (locale_dir / 'sphinx.mo').exists()
+        assert app.translator.gettext('Quick search') == 'QUICK SEARCH'
+
+        app.build()
+        content = (app.outdir / 'index.html').read_text()
+        assert 'QUICK SEARCH' in content
+    finally:
+        locale.translators.clear()
diff --git a/tests/test_pycode_ast.py b/tests/test_pycode_ast.py
index 9b12d24d5..32a784b74 100644
--- a/tests/test_pycode_ast.py
+++ b/tests/test_pycode_ast.py
@@ -53,7 +53,7 @@ from sphinx.pycode import ast
     ("+ a", "+ a"),                             # UAdd
     ("- 1", "- 1"),                             # UnaryOp
     ("- a", "- a"),                             # USub
-    ("(1, 2, 3)", "1, 2, 3"),                   # Tuple
+    ("(1, 2, 3)", "(1, 2, 3)"),                   # Tuple
     ("()", "()"),                               # Tuple (empty)
 ])
 def test_unparse(source, expected):
diff --git a/tests/test_util_typing.py b/tests/test_util_typing.py
index 932fdbfc0..3f8ddbb37 100644
--- a/tests/test_util_typing.py
+++ b/tests/test_util_typing.py
@@ -32,6 +32,10 @@ class MyList(List[T]):
     pass
 
 
+class BrokenType:
+    __args__ = int
+
+
 def test_stringify():
     assert stringify(int) == "int"
     assert stringify(str) == "str"
@@ -113,3 +117,7 @@ def test_stringify_type_hints_alias():
     MyTuple = Tuple[str, str]
     assert stringify(MyStr) == "str"
     assert stringify(MyTuple) == "Tuple[str, str]"  # type: ignore
+
+
+def test_stringify_broken_type_hints():
+    assert stringify(BrokenType) == 'test_util_typing.BrokenType'