diff --git a/Makefile b/Makefile
index bc5d4bab0..6a1a49786 100644
--- a/Makefile
+++ b/Makefile
@@ -5,7 +5,8 @@ CONFIG_DIR     = .
 SPHINXOPTS     = -D project_root=$(ROOT) -D canonical_version=$(CANONICAL_VERSION) \
                  -D versions=$(VERSIONS) -D languages=$(LANGUAGES) -D language=$(CURRENT_LANG) \
                  -D is_remote_build=$(IS_REMOTE_BUILD) \
-                 -A google_analytics_key=$(GOOGLE_ANALYTICS_KEY)
+                 -A google_analytics_key=$(GOOGLE_ANALYTICS_KEY) \
+				 -j auto
 SOURCE_DIR     = content
 BUILD_DIR      = _build
 
diff --git a/conf.py b/conf.py
index 9b6af150a..7b5123524 100644
--- a/conf.py
+++ b/conf.py
@@ -164,9 +164,10 @@ html_favicon = os.path.join(html_theme_path[0], html_theme, 'static', 'img', 'fa
 html_static_path = ['static']
 html_add_permalinks = '¶'  # Sphinx < 3.5
 html_permalinks = True  # Sphinx >= 3.5
-# The page-specific js files that can be imported with the 'custom-js' metadata directive. TODO VFE does it act as a filter? Why are there already some imports not listed here?
+# Additional css & js files:
+# Empty because the js & css files are specified in the extensions/theme
+# or specified for a given page only through the custom-js & custom-css metadata directives
 html_js_files = []
-# The page-specific css files that can be imported with the 'custom-css' metadata directive. TODO VFE does it act as a filter? Why are there already some imports not listed here?
 html_css_files = []
 
 # PHP lexer option to not require <?php
diff --git a/extensions/autodoc_placeholder/__init__.py b/extensions/autodoc_placeholder/__init__.py
index 6508960c4..470f53830 100644
--- a/extensions/autodoc_placeholder/__init__.py
+++ b/extensions/autodoc_placeholder/__init__.py
@@ -19,3 +19,8 @@ def setup(app):
     directives.register_directive('autodata', PlaceHolder)
     directives.register_directive('automethod', PlaceHolder)
     directives.register_directive('autoattribute', PlaceHolder)
+
+    return {
+        'parallel_read_safe': True,
+        'parallel_write_safe': True
+    }
diff --git a/extensions/embedded_video/__init__.py b/extensions/embedded_video/__init__.py
index 186f1908a..f200deeed 100644
--- a/extensions/embedded_video/__init__.py
+++ b/extensions/embedded_video/__init__.py
@@ -61,6 +61,11 @@ class Vimeo(IframeVideo):
     class="align-%(align)s"></iframe>'
 
 
-def setup(builder):
+def setup(app):
     directives.register_directive('youtube', Youtube)
-    directives.register_directive('vimeo', Vimeo)
\ No newline at end of file
+    directives.register_directive('vimeo', Vimeo)
+
+    return {
+        'parallel_read_safe': True,
+        'parallel_write_safe': True
+    }
diff --git a/extensions/exercise_admonition/__init__.py b/extensions/exercise_admonition/__init__.py
index e651c8f30..e16afd94e 100644
--- a/extensions/exercise_admonition/__init__.py
+++ b/extensions/exercise_admonition/__init__.py
@@ -20,5 +20,9 @@ def setup(app):
         lambda self, node: self.depart_admonition(node),
     ))
 
+    return {
+        'parallel_read_safe': True,
+        'parallel_write_safe': True
+    }
 
 admonitionlabels['exercise'] = 'Exercise'
diff --git a/extensions/github_link/__init__.py b/extensions/github_link/__init__.py
index 0457567d8..5d1752c5e 100644
--- a/extensions/github_link/__init__.py
+++ b/extensions/github_link/__init__.py
@@ -74,6 +74,10 @@ def setup(app):
             odoo_repository=True)
     app.config.linkcode_resolve = linkcode_resolve
 
+    return {
+        'parallel_read_safe': True,
+        'parallel_write_safe': True
+    }
 
 def make_github_link(app, path, line=None, mode="blob", odoo_repository=False):
     config = app.config
@@ -110,9 +114,5 @@ def add_doc_link(app, pagename, templatename, context, doctree):
     # may be useful in the future
     source_suffix = app.config.source_suffix
     source_suffix = next(iter(source_suffix))
-    # FIXME: odoo/odoo has a doc/ prefix which is incorrect for this
-    # project, how to unify? Add new setting?
-    # FIXME ANVFE: use a config directive to specify the content folder
-    # instead of hardcoding it here ?
     context['github_link'] = lambda mode='edit': make_github_link(
         app, 'content/%s%s' % (pagename, source_suffix), mode=mode)
diff --git a/extensions/html_domain/__init__.py b/extensions/html_domain/__init__.py
index 53cddc15c..70a38ee79 100644
--- a/extensions/html_domain/__init__.py
+++ b/extensions/html_domain/__init__.py
@@ -39,6 +39,10 @@ def setup(app):
                        ('kbd', kbd), ('var', var), ('samp', samp)]:
         addnode(app, node, name)
 
+    return {
+        'parallel_read_safe': True,
+        'parallel_write_safe': True
+    }
 
 class div(nodes.General, nodes.Element):
     pass
diff --git a/extensions/odoo_theme/__init__.py b/extensions/odoo_theme/__init__.py
index 20a5926d2..4e61aaefb 100644
--- a/extensions/odoo_theme/__init__.py
+++ b/extensions/odoo_theme/__init__.py
@@ -15,6 +15,10 @@ def setup(app):
     app.add_js_file('js/menu.js')
     app.add_js_file('js/page_toc.js')
 
+    return {
+        'parallel_read_safe': True,
+        'parallel_write_safe': True
+    }
 
 def set_missing_meta(app, pagename, templatename, context, doctree):
     if context.get('meta') is None:  # Pages without title (used with `include::`) have no meta
diff --git a/extensions/odoo_theme/layout.html b/extensions/odoo_theme/layout.html
index 70007992a..20d38f0bf 100644
--- a/extensions/odoo_theme/layout.html
+++ b/extensions/odoo_theme/layout.html
@@ -3,17 +3,18 @@
 
 {% block css %}
     {{ super() }}
-    {# Allow custom css style import for specific pages #}
-    {% if 'custom-css' in meta %}
-        {# TODO VFE this should be wrapped in a loop as custom-css is a comma(, not ;)-separated list #}
-        {% set link = '_static/css/' + meta['custom-css'] %}
-        <link rel="stylesheet" href="{{ pathto(link, 1) }}" type="text/css"/>
+    {% if 'custom-css' in meta %}{# Allow custom css style import for specific pages #}
+        {% set css_files = meta['custom-css'].split(',') %}
+        {% for css_file in css_files %}
+            {% set link = '_static/css/' + css_file %}
+            <link rel="stylesheet" href="{{ pathto(link, 1) }}" type="text/css"/>
+        {% endfor %}
     {% endif %}
 {% endblock %}
 
 {% block scripts %}
-    {% if 'custom-js' in meta %}
-        {# Before the custom files using React & Immutable #}
+    {% if 'custom-js' in meta %}{# Allow custom js import for specific pages #}
+        {# Before the custom files using React & Immutable (accounting mementos) #}
         <script src="https://cdnjs.cloudflare.com/ajax/libs/immutable/3.8.2/immutable.min.js"
             integrity="sha512-myCdDiGJRYrvRb/VuJ67ljifYTJdc1jdEvL4c4ftX9o3N6EAnmD83c/7l2/91RCINZ7c8w21tiXDT7RDFjdc3g=="
             crossorigin="anonymous"></script>
@@ -27,13 +28,10 @@
             <script src="{{ pathto(link, 1) }}"></script>
         {% endfor %}
     {% endif %}
-    {# FIXME ANVFEDI Do we really need prefixfree ? It triggers a reload of css files two more times/page #}
-    <!-- <script src="https://cdn.jsdelivr.net/npm/prefixfree@1.0.0/prefixfree.min.js"
-        integrity="sha256-a1jYldRqTzpGqk63nmXXjh/zPYp7Sjxp9iUYhNbYPXI="
-        crossorigin="anonymous"></script> -->
-    {{ super() }}
-    {# TODO EDI boostrap beta cdn ??? Isn't there a stable CDN ? It looks like this cdn won't exist forever :D #}
-    <script src="https://cdn.jsdelivr.net/npm/bootstrap@5.0.0-beta2/dist/js/bootstrap.bundle.min.js" integrity="sha384-b5kHyXgcpbZJO/tY9Ul7kGkf1S0CWuKcCD38l8YkeH8z8QjE0GmW1gYU5S9FOnJ0" crossorigin="anonymous"></script>
+    {{ super() }} {# Load the scripts specified in the extensions/themes #}
+    <script src="https://cdn.jsdelivr.net/npm/bootstrap@5.0.0-beta2/dist/js/bootstrap.bundle.min.js"
+        integrity="sha384-b5kHyXgcpbZJO/tY9Ul7kGkf1S0CWuKcCD38l8YkeH8z8QjE0GmW1gYU5S9FOnJ0"
+        crossorigin="anonymous"></script>
 {% endblock %}
 
 {% block linktags %}
@@ -55,12 +53,12 @@
 {% endblock %}
 
 {% block header %}
-    {# shown when js has properly set all the classes on the toc elements #}
     <noscript>
         <nav class="o_side_nav border-end">
             {% include "layout_templates/menu.html" %}
         </nav>
     </noscript>
+    {# shown when js has properly set all the classes on the toc elements #}
     <nav id="o_main_toctree" class="o_side_nav border-end" hidden>
         {% include "layout_templates/menu.html" %}
     </nav>
@@ -103,11 +101,9 @@
                 {% include "layout_templates/homepage.html" %}
             {% else %}
                 <article id="o_content" class="doc-body">
-                    <!-- Beacon used by the Sphinx search to know where to look for a string -->
-                    <div role="main">
+                    <div role="main">{# Beacon used by the Sphinx search to know where to look for a string #}
                         {% block body %} {% endblock %}
                     </div>
-                    {# Do not show the edition link for pages without content #}
                     {% if github_link and pagename != 'search' %}
                         <a href="{{ github_link(mode='edit') }}" class="o_git_link d-none d-lg-inline-block"><i class="i-edit"></i> Edit on GitHub</a>
                     {% endif %}
diff --git a/extensions/odoo_theme/static/js/utils.js b/extensions/odoo_theme/static/js/utils.js
index 4909204d4..63274e12e 100644
--- a/extensions/odoo_theme/static/js/utils.js
+++ b/extensions/odoo_theme/static/js/utils.js
@@ -1,4 +1,4 @@
-let tocEntryListId = 0;  // Used to generate IDs of toc entry lists for both the menu and page TOC
+let tocEntryListId = 0; // Used to generate IDs of toc entry lists for both the menu and page TOC
 
 /**
  * Update the provided TOC to allow collapsing its entries with Bootstrap's accordion.
@@ -42,7 +42,7 @@ const _prepareAccordion = (tocElement) => {
     const tocRoot = tocElement.querySelector('ul');
     tocRoot.querySelectorAll('ul').forEach(tocEntryList => {
         // Modify the <ul> element
-        tocEntryList.id = `o_target_${tocEntryListId++}`
+        tocEntryList.id = `o_target_${tocEntryListId++}`;
         tocEntryList.classList.add('collapse');
         // Create and configure an <i> element
         const arrowButton = document.createElement('I');
@@ -62,4 +62,4 @@ const _prepareAccordion = (tocElement) => {
         tocEntryWrapper.append(arrowButton, relatedHeadingRef);
         tocEntryList.parentNode.insertBefore(tocEntryWrapper, tocEntryList);
     });
-};
\ No newline at end of file
+};
diff --git a/extensions/odoo_theme/translator.py b/extensions/odoo_theme/translator.py
index 637082d99..99f85d920 100644
--- a/extensions/odoo_theme/translator.py
+++ b/extensions/odoo_theme/translator.py
@@ -76,9 +76,6 @@ class BootstrapTranslator(HTML5Translator):
         self.context = []
         self.section_level = 0
 
-        # self.config = self.builder.config
-        # self.highlightlang = self.highlightlang_base = self.builder.config.highlight_language
-
         self.first_param = 1
         self.param_separator = ','
 
@@ -91,32 +88,17 @@ class BootstrapTranslator(HTML5Translator):
             0xa0: u'&nbsp;'
         })
 
-    # def add_meta(self, meta):
-    #     self.meta.append('\n    ' + meta)
-
-    # only "space characters" SPACE, CHARACTER TABULATION, LINE FEED,
-    # FORM FEED and CARRIAGE RETURN should be collapsed, not al White_Space
-
-
     def unknown_visit(self, node):
         print("unknown node", node.__class__.__name__)
         self.body.append(u'[UNKNOWN NODE {}]'.format(node.__class__.__name__))
         raise nodes.SkipNode
 
-    # VFE NOTE: seems that when we remove/comment this, we get 5 times the tiles in the global toc :D
+    # VFE NOTE: seems that when we remove/comment this, we get the titles 5 timesin the global toc :D
     def visit_document(self, node):
         self.first_title = True
     def depart_document(self, node):
         pass
 
-    # def visit_meta(self, node):
-    #     if node.hasattr('lang'):
-    #         node['xml:lang'] = node['lang']
-    #     meta = self.starttag(node, 'meta', **node.non_default_attributes())
-    #     self.add_meta(meta)
-    # def depart_meta(self, node):
-    #     pass
-
     # Breaks Accounting memento if commented
     def visit_section(self, node):
         # close "parent" or preceding section, unless this is the opening of
@@ -132,13 +114,6 @@ class BootstrapTranslator(HTML5Translator):
         if not self.section_level:
             self.body.append(u'</section>')
 
-    # # VFE FIXME do we need to keep this logic ?
-    # # Seems that the only change is the use of a nav instead of a div.
-    # def visit_topic(self, node):
-    #     self.body.append(self.starttag(node, 'nav'))
-    # def depart_topic(self, node):
-    #     self.body.append(u'</nav>')
-
     # overwritten
     # Class mapping:
     # admonition [name] -> alert-[name]
@@ -185,415 +160,3 @@ class BootstrapTranslator(HTML5Translator):
             classes.append('align-%s' % node['align'])
         tag = self.starttag(node, 'table', CLASS=' '.join(classes))
         self.body.append(tag)
-
-    # def is_compact_paragraph(self, node):
-    #     parent = node.parent
-    #     if isinstance(parent, (nodes.document, nodes.compound,
-    #                            addnodes.desc_content,
-    #                            addnodes.versionmodified)):
-    #         # Never compact paragraphs in document or compound.
-    #         return False
-
-    #     for key, value in node.attlist():
-    #         # we can ignore a few specific classes, all other non-default
-    #         # attributes require that a <p> node remains
-    #         if key != 'classes' or value not in ([], ['first'], ['last'], ['first', 'last']):
-    #             return False
-
-    #     first = isinstance(node.parent[0], nodes.label)
-    #     for child in parent.children[first:]:
-    #         # only first paragraph can be compact
-    #         if isinstance(child, nodes.Invisible):
-    #             continue
-    #         if child is node:
-    #             break
-    #         return False
-    #     parent_length = len([
-    #         1 for n in parent
-    #         if not isinstance(n, (nodes.Invisible, nodes.label))
-    #     ])
-    #     return parent_length == 1
-
-    # def visit_paragraph(self, node):
-    #     if self.is_compact_paragraph(node):
-    #         self.context.append(u'')
-    #         return
-    #     self.body.append(self.starttag(node, 'p'))
-    #     self.context.append(u'</p>')
-    # def depart_paragraph(self, node):
-    #     self.body.append(self.context.pop())
-
-    # def visit_problematic(self, node):
-    #     if node.hasattr('refid'):
-    #         self.body.append('<a href="#%s">' % node['refid'])
-    #         self.context.append('</a>')
-    #     else:
-    #         self.context.append('')
-    #     self.body.append(self.starttag(node, 'span', CLASS='problematic'))
-
-    # def depart_problematic(self, node):
-    #     self.body.append('</span>')
-    #     self.body.append(self.context.pop())
-
-    # def visit_bullet_list(self, node):
-    #     self.body.append(self.starttag(node, 'ul'))
-    # def depart_bullet_list(self, node):
-    #     self.body.append(u'</ul>')
-    # def visit_enumerated_list(self, node):
-    #     self.body.append(self.starttag(node, 'ol'))
-    # def depart_enumerated_list(self, node):
-    #     self.body.append(u'</ol>')
-    # def visit_list_item(self, node):
-    #     self.body.append(self.starttag(node, 'li'))
-    # def depart_list_item(self, node):
-    #     self.body.append(u'</li>')
-    # def visit_definition_list(self, node):
-    #     self.body.append(self.starttag(node, 'dl'))
-    # def depart_definition_list(self, node):
-    #     self.body.append(u'</dl>')
-    # def visit_definition_list_item(self, node):
-    #     pass
-    # def depart_definition_list_item(self, node):
-    #     pass
-    # def visit_term(self, node):
-    #     self.body.append(self.starttag(node, 'dt'))
-    # def depart_term(self, node):
-    #     self.body.append(u'</dt>')
-    # def visit_termsep(self, node):
-    #     self.body.append(self.starttag(node, 'br'))
-    #     raise nodes.SkipNode
-    # def visit_definition(self, node):
-    #     self.body.append(self.starttag(node, 'dd'))
-    # def depart_definition(self, node):
-    #     self.body.append(u'</dd>')
-
-    # def visit_admonition(self, node, type=None):
-    #     clss = {
-    #         # ???: 'alert-success',
-
-    #         'note': 'alert-info',
-    #         'hint': 'alert-info',
-    #         'tip': 'alert-info',
-    #         'seealso': 'alert-go_to',
-
-    #         'warning': 'alert-warning',
-    #         'attention': 'alert-warning',
-    #         'caution': 'alert-warning',
-    #         'important': 'alert-warning',
-
-    #         'danger': 'alert-danger',
-    #         'error': 'alert-danger',
-
-    #         'exercise': 'alert-exercise',
-    #     }
-    #     self.body.append(self.starttag(node, 'div', role='alert', CLASS='alert {}'.format(
-    #         clss.get(type, '')
-    #     )))
-    #     if 'alert-dismissible' in node.get('classes', []):
-    #         self.body.append(
-    #             u'<button type="button" class="close" data-dismiss="alert" aria-label="Close">'
-    #             u'<span aria-hidden="true">&times;</span>'
-    #             u'</button>')
-    #     if type:
-    #         node.insert(0, nodes.title(type, admonitionlabels[type]))
-    # def depart_admonition(self, node):
-    #     self.body.append(u'</div>')
-
-    # def visit_versionmodified(self, node):
-    #     self.body.append(self.starttag(node, 'div', CLASS=node['type']))
-    # def depart_versionmodified(self, node):
-    #     self.body.append(u'</div>')
-
-    # # the rubric should be a smaller heading than the current section, up to
-    # # h6... maybe "h7" should be a ``p`` instead?
-    # def visit_rubric(self, node):
-    #     self.body.append(self.starttag(node, 'h{}'.format(min(self.section_level + 1, 6))))
-    # def depart_rubric(self, node):
-    #     self.body.append(u'</h{}>'.format(min(self.section_level + 1, 6)))
-
-    # # one more div in the base class: keep it?
-    # # def visit_block_quote(self, node):
-    # #     self.body.append(self.starttag(node, 'blockquote'))
-    # # def depart_block_quote(self, node):
-    # #     self.body.append(u'</blockquote>')
-    # def visit_attribution(self, node):
-    #     self.body.append(self.starttag(node, 'footer'))
-    # def depart_attribution(self, node):
-    #     self.body.append(u'</footer>')
-
-    # def visit_container(self, node):
-    #     self.body.append(self.starttag(node, 'div'))
-    # def depart_container(self, node):
-    #     self.body.append(u'</div>')
-    # def visit_compound(self, node):
-    #     self.body.append(self.starttag(node, 'div'))
-    # def depart_compound(self, node):
-    #     self.body.append(u'</div>')
-
-    # # overwritten, check if super can still be used
-    # def visit_image(self, node):
-    #     uri = node['uri']
-    #     if uri in self.builder.images:
-    #         uri = posixpath.join(self.builder.imgpath,
-    #                              self.builder.images[uri])
-    #     attrs = {'src': uri, 'class': 'img-fluid'}
-    #     if 'alt' in node:
-    #         attrs['alt'] = node['alt']
-    #     if 'align' in node:
-    #         if node['align'] == 'center':
-    #             attrs['class'] += ' center-block'
-    #         else:
-    #             doc = None
-    #             if node.source:
-    #                 doc = node.source
-    #                 if node.line:
-    #                     doc += ':%d' % node.line
-    #             self.builder.app.warn(
-    #                 "Unsupported alignment value \"%s\"" % node['align'],
-    #                 location=doc
-    #             )
-    #     elif 'align' in node.parent and node.parent['align'] == 'center':
-    #         # figure > image
-    #         attrs['class'] += ' center-block'
-
-    #     # todo: explicit width/height/scale?
-    #     self.body.append(self.starttag(node, 'img', **attrs))
-    # def depart_image(self, node): pass
-    # def visit_figure(self, node):
-    #     self.body.append(self.starttag(node, 'div'))
-    # def depart_figure(self, node):
-    #     self.body.append(u'</div>')
-    # # def visit_caption(self, node):
-    # #     # first paragraph of figure content
-    # #     self.body.append(self.starttag(node, 'h4'))
-    # # def depart_caption(self, node):
-    # #     self.body.append(u'</h4>')
-    # def visit_legend(self, node): pass
-    # def depart_legend(self, node): pass
-
-    # def visit_line(self, node):
-    #     self.body.append(self.starttag(node, 'div', CLASS='line'))
-    #     # ensure the line still takes the room it needs
-    #     if not len(node): self.body.append(u'<br />')
-    # def depart_line(self, node):
-    #     self.body.append(u'</div>')
-
-    # def visit_line_block(self, node):
-    #     self.body.append(self.starttag(node, 'div', CLASS='line-block'))
-    # def depart_line_block(self, node):
-    #     self.body.append(u'</div>')
-
-    # # def visit_table(self, node):
-    # #     self.body.append(self.starttag(node, 'table', CLASS='table'))
-    # # def depart_table(self, node):
-    # #     self.body.append(u'</table>')
-    # def visit_tgroup(self, node): pass
-    # def depart_tgroup(self, node): pass
-    # def visit_colspec(self, node): raise nodes.SkipNode
-    # def visit_thead(self, node):
-    #     self.body.append(self.starttag(node, 'thead'))
-    # def depart_thead(self, node):
-    #     self.body.append(u'</thead>')
-    # def visit_tbody(self, node):
-    #     self.body.append(self.starttag(node, 'tbody'))
-    # def depart_tbody(self, node):
-    #     self.body.append(u'</tbody>')
-    # def visit_row(self, node):
-    #     self.body.append(self.starttag(node, 'tr'))
-    # def depart_row(self, node):
-    #     self.body.append(u'</tr>')
-    # def visit_entry(self, node):
-    #     if isinstance(node.parent.parent, nodes.thead):
-    #         tagname = 'th'
-    #     else:
-    #         tagname = 'td'
-    #     self.body.append(self.starttag(node, tagname))
-    #     self.context.append(tagname)
-    # def depart_entry(self, node):
-    #     self.body.append(u'</{}>'.format(self.context.pop()))
-
-    # # def visit_Text(self, node):
-    # #     self.body.append(self.encode(node.astext()))
-    # # def depart_Text(self, node):
-    # #     pass
-    # def visit_literal(self, node):
-    #     self.body.append(self.starttag(node, 'code'))
-    # def depart_literal(self, node):
-    #     self.body.append(u'</code>')
-    # visit_literal_emphasis = visit_literal
-    # depart_literal_emphasis = depart_literal
-    # def visit_emphasis(self, node):
-    #     self.body.append(self.starttag(node, 'em'))
-    # def depart_emphasis(self, node):
-    #     self.body.append(u'</em>')
-    # def visit_strong(self, node):
-    #     self.body.append(self.starttag(node, 'strong'))
-    # def depart_strong(self, node):
-    #     self.body.append(u'</strong>')
-    # visit_literal_strong = visit_strong
-    # depart_literal_strong = depart_strong
-    # def visit_inline(self, node):
-    #     self.body.append(self.starttag(node, 'span'))
-    # def depart_inline(self, node):
-    #     self.body.append(u'</span>')
-
-    # # def visit_download_reference(self, node):
-    # #     # type: (nodes.Node) -> None
-    # #     if node.hasattr('filename'):
-    # #         self.body.append(
-    # #             '<a class="reference download internal" href="%s" download="">' %
-    # #             posixpath.join(self.builder.dlpath, node['filename']))
-    # #         self.body.append(node.astext())
-    # #         self.body.append('</a>')
-    # #         raise nodes.SkipNode
-    # #     else:
-    # #         self.context.append('')
-    # # def depart_download_reference(self, node):
-    # #     # type: (nodes.Node) -> None
-    # #     self.body.append(self.context.pop())
-    # def visit_target(self, node): pass
-    # def depart_target(self, node): pass
-    # def visit_footnote(self, node):
-    #     self.body.append(self.starttag(node, 'div', CLASS='footnote'))
-    #     self.footnote_backrefs(node)
-    # def depart_footnote(self, node):
-    #     self.body.append(u'</div>')
-    # def visit_footnote_reference(self, node):
-    #     self.body.append(self.starttag(
-    #         node, 'a', href='#' + node['refid'], CLASS="footnote-ref"))
-    # def depart_footnote_reference(self, node):
-    #     self.body.append(u'</a>')
-    # def visit_label(self, node):
-    #     self.body.append(self.starttag(node, 'span', CLASS='footnote-label'))
-    #     self.body.append(u'%s[' % self.context.pop())
-    # def depart_label(self, node):
-    #     # Context added in footnote_backrefs.
-    #     self.body.append(u']%s</span> %s' % (self.context.pop(), self.context.pop()))
-    # def footnote_backrefs(self, node):
-    #     # should store following data on context stack (in that order since
-    #     # they'll be popped so LIFO)
-    #     #
-    #     # * outside (after) label
-    #     # * after label text
-    #     # * before label text
-    #     backrefs = node['backrefs']
-    #     if not backrefs:
-    #         self.context.extend(['', '', ''])
-    #     elif len(backrefs) == 1:
-    #         self.context.extend([
-    #             '',
-    #             '</a>',
-    #             '<a class="footnote-backref" href="#%s">' % backrefs[0]
-    #         ])
-    #     else:
-    #         backlinks = (
-    #             '<a class="footnote-backref" href="#%s">%s</a>' % (backref, i)
-    #             for i, backref in enumerate(backrefs, start=1)
-    #         )
-    #         self.context.extend([
-    #             '<em class="footnote-backrefs">(%s)</em> ' % ', '.join(backlinks),
-    #             '',
-    #             ''
-    #         ])
-
-    # def visit_desc(self, node):
-    #     self.body.append(self.starttag(node, 'section', CLASS='code-' + node['objtype']))
-    # def depart_desc(self, node):
-    #     self.body.append(u'</section>')
-    # def visit_desc_signature(self, node):
-    #     self.body.append(self.starttag(node, 'h6'))
-    #     self.body.append(u'<code>')
-    # def depart_desc_signature(self, node):
-    #     self.body.append(u'</code>')
-    #     self.body.append(u'</h6>')
-    # def visit_desc_addname(self, node): pass
-    # def depart_desc_addname(self, node): pass
-    # def visit_desc_type(self, node): pass
-    # def depart_desc_type(self, node): pass
-    # def visit_desc_returns(self, node):
-    #     self.body.append(u' → ')
-    # def depart_desc_returns(self, node):
-    #     pass
-    # def visit_desc_name(self, node): pass
-    # def depart_desc_name(self, node): pass
-    # def visit_desc_parameterlist(self, node):
-    #     self.body.append(u'(')
-    #     self.first_param = True
-    #     self.optional_param_level = 0
-    #     # How many required parameters are left.
-    #     self.required_params_left = sum(isinstance(c, addnodes.desc_parameter) for c in node.children)
-    #     self.param_separator = node.child_text_separator
-    # def depart_desc_parameterlist(self, node):
-    #     self.body.append(u')')
-    # # If required parameters are still to come, then put the comma after
-    # # the parameter.  Otherwise, put the comma before.  This ensures that
-    # # signatures like the following render correctly (see issue #1001):
-    # #
-    # #     foo([a, ]b, c[, d])
-    # #
-    # def visit_desc_parameter(self, node):
-    #     if self.first_param:
-    #         self.first_param = 0
-    #     elif not self.required_params_left:
-    #         self.body.append(self.param_separator)
-    #     if self.optional_param_level == 0:
-    #         self.required_params_left -= 1
-    #     if 'noemph' not in node: self.body.append(u'<em>')
-    # def depart_desc_parameter(self, node):
-    #     if 'noemph' not in node: self.body.append(u'</em>')
-    #     if self.required_params_left:
-    #         self.body.append(self.param_separator)
-    # def visit_desc_optional(self, node):
-    #     self.optional_param_level += 1
-    #     self.body.append(u'[')
-    # def depart_desc_optional(self, node):
-    #     self.optional_param_level -= 1
-    #     self.body.append(u']')
-    # def visit_desc_annotation(self, node):
-    #     self.body.append(self.starttag(node, 'em'))
-    # def depart_desc_annotation(self, node):
-    #     self.body.append(u'</em>')
-    # def visit_desc_content(self, node): pass
-    # def depart_desc_content(self, node): pass
-    # def visit_field_list(self, node):
-    #      self.body.append(self.starttag(node, 'div', CLASS='code-fields'))
-    # def depart_field_list(self, node):
-    #     self.body.append(u'</div>')
-    # def visit_field(self, node):
-    #     self.body.append(self.starttag(node, 'div', CLASS='code-field'))
-    # def depart_field(self, node):
-    #     self.body.append(u'</div>')
-    # def visit_field_name(self, node):
-    #     self.body.append(self.starttag(node, 'div', CLASS='code-field-name'))
-    # def depart_field_name(self, node):
-    #     self.body.append(u'</div>')
-    # def visit_field_body(self, node):
-    #     self.body.append(self.starttag(node, 'div', CLASS='code-field-body'))
-    # def depart_field_body(self, node):
-    #     self.body.append(u'</div>')
-
-    # def visit_raw(self, node):
-    #     if 'html' in node.get('format', '').split():
-    #         t = 'span' if isinstance(node.parent, nodes.TextElement) else 'div'
-    #         if node['classes']:
-    #             self.body.append(self.starttag(node, t))
-    #         self.body.append(node.astext())
-    #         if node['classes']:
-    #             self.body.append('</%s>' % t)
-    #     # Keep non-HTML raw text out of output:
-    #     raise nodes.SkipNode
-
-    # # internal node
-    # def visit_substitution_definition(self, node): raise nodes.SkipNode
-
-    # # without set_translator, add_node doesn't work correctly, so the
-    # # serialization of html_domain nodes needs to be embedded here
-    # def visit_div(self, node):
-    #     self.body.append(self.starttag(node, 'div'))
-    # def depart_div(self, node):
-    #     self.body.append(u'</div>\n')
-    # def visit_address(self, node):
-    #     self.body.append(self.starttag(node, 'address'))
-    # def depart_address(self, node):
-    #     self.body.append(u'</address>')
-    # # TODO: inline elements
diff --git a/extensions/redirects/__init__.py b/extensions/redirects/__init__.py
index a4c670341..054baf733 100644
--- a/extensions/redirects/__init__.py
+++ b/extensions/redirects/__init__.py
@@ -62,3 +62,8 @@ def generate_redirects(app):
 def setup(app):
     app.add_config_value('redirects_file', 'redirects', 'env')
     app.connect('builder-inited', generate_redirects)
+
+    return {
+        'parallel_read_safe': True,
+        'parallel_write_safe': True
+    }
diff --git a/extensions/switcher/__init__.py b/extensions/switcher/__init__.py
index f21be0829..7ae9b3376 100644
--- a/extensions/switcher/__init__.py
+++ b/extensions/switcher/__init__.py
@@ -12,6 +12,11 @@ def setup(app):
 
     app.connect('env-updated', add_statics)
 
+    return {
+        'parallel_read_safe': True,
+        'parallel_write_safe': True
+    }
+
 def add_statics(app, env):
     app.add_js_file('js/switcher.js')
     env.config.html_static_path.append(statics())