diff --git a/src/doc/not_found.md b/src/doc/not_found.md
index f0794fc0be3..9552759d2b8 100644
--- a/src/doc/not_found.md
+++ b/src/doc/not_found.md
@@ -2,7 +2,7 @@
 
 <!-- Completely hide the TOC and the section numbers -->
 <style type="text/css">
-#TOC { display: none; }
+#rustdoc-toc { display: none; }
 .header-section-number { display: none; }
 li {list-style-type: none; }
 #search-input {
diff --git a/src/librustdoc/html/markdown.rs b/src/librustdoc/html/markdown.rs
index 4b82f232765..5da492f7c6f 100644
--- a/src/librustdoc/html/markdown.rs
+++ b/src/librustdoc/html/markdown.rs
@@ -1452,7 +1452,7 @@ impl MarkdownWithToc<'_> {
     }
     pub(crate) fn into_string(self) -> String {
         let (toc, s) = self.into_parts();
-        format!("<nav id=\"TOC\">{toc}</nav>{s}", toc = toc.print())
+        format!("<nav id=\"rustdoc\">{toc}</nav>{s}", toc = toc.print())
     }
 }
 
@@ -2028,7 +2028,8 @@ fn init_id_map() -> FxHashMap<Cow<'static, str>, usize> {
     map.insert("default-settings".into(), 1);
     map.insert("sidebar-vars".into(), 1);
     map.insert("copy-path".into(), 1);
-    map.insert("TOC".into(), 1);
+    map.insert("rustdoc-toc".into(), 1);
+    map.insert("rustdoc-modnav".into(), 1);
     // This is the list of IDs used by rustdoc sections (but still generated by
     // rustdoc).
     map.insert("fields".into(), 1);
diff --git a/src/librustdoc/html/static/css/rustdoc.css b/src/librustdoc/html/static/css/rustdoc.css
index c2bb5fa8f2a..32077e0b7f9 100644
--- a/src/librustdoc/html/static/css/rustdoc.css
+++ b/src/librustdoc/html/static/css/rustdoc.css
@@ -589,11 +589,11 @@ ul.block, .block li, .block ul {
 	background-clip: border-box;
 }
 
-.hide-toc #TOC, .hide-toc .in-crate {
+.hide-toc #rustdoc-toc, .hide-toc .in-crate {
 	display: none;
 }
 
-.hide-modnav #ModNav {
+.hide-modnav #rustdoc-modnav {
 	display: none;
 }
 
diff --git a/src/librustdoc/html/static/js/main.js b/src/librustdoc/html/static/js/main.js
index 4135341b22e..5a0796e2353 100644
--- a/src/librustdoc/html/static/js/main.js
+++ b/src/librustdoc/html/static/js/main.js
@@ -499,7 +499,7 @@ function preLoadCss(cssUrl) {
         if (!window.SIDEBAR_ITEMS) {
             return;
         }
-        const sidebar = document.getElementById("ModNav");
+        const sidebar = document.getElementById("rustdoc-modnav");
 
         /**
          * Append to the sidebar a "block" of links - a heading along with a list (`<ul>`) of items.
@@ -885,7 +885,7 @@ function preLoadCss(cssUrl) {
         if (!window.ALL_CRATES) {
             return;
         }
-        const sidebarElems = document.getElementById("ModNav");
+        const sidebarElems = document.getElementById("rustdoc-modnav");
         if (!sidebarElems) {
             return;
         }
diff --git a/src/librustdoc/html/templates/sidebar.html b/src/librustdoc/html/templates/sidebar.html
index 31823848ec3..fccf65cbefc 100644
--- a/src/librustdoc/html/templates/sidebar.html
+++ b/src/librustdoc/html/templates/sidebar.html
@@ -6,7 +6,7 @@
     {% endif %}
 
     {% if self.should_render_blocks() %}
-        <section id="TOC">
+        <section id="rustdoc-toc">
             {% if !title.is_empty() %}
             <h2 class="location"> {# #}
                 <a href="#">{{title_prefix}}{{title|wrapped|safe}}</a> {# #}
@@ -53,7 +53,7 @@
             {% endfor %}
         </section>
     {% endif %}
-    <div id="ModNav">
+    <div id="rustdoc-modnav">
     {% if !path.is_empty() %}
         <h2{% if parent_is_crate +%} class="in-crate"{% endif %}> {# #}
             <a href="{% if is_mod %}../{% endif %}index.html">In {{+ path|wrapped|safe}}</a> {# #}
diff --git a/tests/rustdoc-gui/sidebar.goml b/tests/rustdoc-gui/sidebar.goml
index 3253e6ea86a..7794cdbe9e2 100644
--- a/tests/rustdoc-gui/sidebar.goml
+++ b/tests/rustdoc-gui/sidebar.goml
@@ -126,8 +126,8 @@ assert-text: (".sidebar-elems ul.block > li.current > a", "module")
 //   - Module name, followed by TOC for module headings
 //   - "In crate [name]" parent pointer, followed by sibling navigation
 assert-count: (".sidebar h2", 3)
-assert-text: (".sidebar > .sidebar-elems > #ModNav > h2", "In crate lib2")
-assert-property: (".sidebar > .sidebar-elems > #ModNav > h2 > a", {
+assert-text: (".sidebar > .sidebar-elems > #rustdoc-modnav > h2", "In crate lib2")
+assert-property: (".sidebar > .sidebar-elems > #rustdoc-modnav > h2 > a", {
     "href": "/lib2/index.html",
 }, ENDS_WITH)
 // We check that we don't have the crate list.
@@ -137,8 +137,8 @@ go-to: "./sub_module/sub_sub_module/index.html"
 assert-property: (".sidebar", {"clientWidth": "200"})
 assert-text: (".sidebar > .sidebar-crate > h2 > a", "lib2")
 assert-text: (".sidebar .location", "Module sub_sub_module")
-assert-text: (".sidebar > .sidebar-elems > #ModNav > h2", "In lib2::module::sub_module")
-assert-property: (".sidebar > .sidebar-elems > #ModNav > h2 > a", {
+assert-text: (".sidebar > .sidebar-elems > #rustdoc-modnav > h2", "In lib2::module::sub_module")
+assert-property: (".sidebar > .sidebar-elems > #rustdoc-modnav > h2 > a", {
     "href": "/module/sub_module/index.html",
 }, ENDS_WITH)
 assert-text: (".sidebar-elems ul.block > li.current > a", "sub_sub_module")
@@ -202,32 +202,32 @@ assert-position: (".sidebar-crate > h2 > a", {"x": -3})
 // Configuration option to show TOC in sidebar.
 set-local-storage: {"rustdoc-hide-toc": "true"}
 go-to: "file://" + |DOC_PATH| + "/test_docs/enum.WhoLetTheDogOut.html"
-assert-css: ("#TOC", {"display": "none"})
+assert-css: ("#rustdoc-toc", {"display": "none"})
 assert-css: (".sidebar .in-crate", {"display": "none"})
 set-local-storage: {"rustdoc-hide-toc": "false"}
 go-to: "file://" + |DOC_PATH| + "/test_docs/enum.WhoLetTheDogOut.html"
-assert-css: ("#TOC", {"display": "block"})
+assert-css: ("#rustdoc-toc", {"display": "block"})
 assert-css: (".sidebar .in-crate", {"display": "block"})
 
 set-local-storage: {"rustdoc-hide-modnav": "true"}
 go-to: "file://" + |DOC_PATH| + "/test_docs/enum.WhoLetTheDogOut.html"
-assert-css: ("#ModNav", {"display": "none"})
+assert-css: ("#rustdoc-modnav", {"display": "none"})
 set-local-storage: {"rustdoc-hide-modnav": "false"}
 go-to: "file://" + |DOC_PATH| + "/test_docs/enum.WhoLetTheDogOut.html"
-assert-css: ("#ModNav", {"display": "block"})
+assert-css: ("#rustdoc-modnav", {"display": "block"})
 
 set-local-storage: {"rustdoc-hide-toc": "true"}
 go-to: "file://" + |DOC_PATH| + "/test_docs/index.html"
-assert-css: ("#TOC", {"display": "none"})
+assert-css: ("#rustdoc-toc", {"display": "none"})
 assert-false: ".sidebar .in-crate"
 set-local-storage: {"rustdoc-hide-toc": "false"}
 go-to: "file://" + |DOC_PATH| + "/test_docs/index.html"
-assert-css: ("#TOC", {"display": "block"})
+assert-css: ("#rustdoc-toc", {"display": "block"})
 assert-false: ".sidebar .in-crate"
 
 set-local-storage: {"rustdoc-hide-modnav": "true"}
 go-to: "file://" + |DOC_PATH| + "/test_docs/index.html"
-assert-css: ("#ModNav", {"display": "none"})
+assert-css: ("#rustdoc-modnav", {"display": "none"})
 set-local-storage: {"rustdoc-hide-modnav": "false"}
 go-to: "file://" + |DOC_PATH| + "/test_docs/index.html"
-assert-css: ("#ModNav", {"display": "block"})
+assert-css: ("#rustdoc-modnav", {"display": "block"})
diff --git a/tests/rustdoc/sidebar/module.rs b/tests/rustdoc/sidebar/module.rs
index 926af71ddfb..b5bcb9f232c 100644
--- a/tests/rustdoc/sidebar/module.rs
+++ b/tests/rustdoc/sidebar/module.rs
@@ -1,16 +1,16 @@
 #![crate_name = "foo"]
 
 //@ has 'foo/index.html'
-//@ has - '//section[@id="TOC"]/h3' 'Crate Items'
+//@ has - '//section[@id="rustdoc-toc"]/h3' 'Crate Items'
 
 //@ has 'foo/bar/index.html'
-//@ has - '//section[@id="TOC"]/h3' 'Module Items'
+//@ has - '//section[@id="rustdoc-toc"]/h3' 'Module Items'
 pub mod bar {
     //@ has 'foo/bar/struct.Baz.html'
-    //@ !has - '//section[@id="TOC"]/h3' 'Module Items'
+    //@ !has - '//section[@id="rustdoc-toc"]/h3' 'Module Items'
     pub struct Baz;
 }
 
 //@ has 'foo/baz/index.html'
-//@ !has - '//section[@id="TOC"]/h3' 'Module Items'
+//@ !has - '//section[@id="rustdoc-toc"]/h3' 'Module Items'
 pub mod baz {}
diff --git a/tests/rustdoc/sidebar/top-toc-html.rs b/tests/rustdoc/sidebar/top-toc-html.rs
index 8991ed0330e..0f603960434 100644
--- a/tests/rustdoc/sidebar/top-toc-html.rs
+++ b/tests/rustdoc/sidebar/top-toc-html.rs
@@ -14,10 +14,10 @@
 
 //@ has foo/index.html
 // User header
-//@ has - '//section[@id="TOC"]/h3' 'Sections'
-//@ has - '//section[@id="TOC"]/ul[@class="block top-toc"]/li/a[@href="#basic-link-emphasis-very-emphasis-and-code"]/@title' 'Basic link, emphasis, very emphasis and `code`'
-//@ has - '//section[@id="TOC"]/ul[@class="block top-toc"]/li/a[@href="#basic-link-emphasis-very-emphasis-and-code"]' 'Basic link, emphasis, very emphasis and code'
-//@ count - '//section[@id="TOC"]/ul[@class="block top-toc"]/li/a[@href="#basic-link-emphasis-very-emphasis-and-code"]/em' 0
-//@ count - '//section[@id="TOC"]/ul[@class="block top-toc"]/li/a[@href="#basic-link-emphasis-very-emphasis-and-code"]/a' 0
-//@ count - '//section[@id="TOC"]/ul[@class="block top-toc"]/li/a[@href="#basic-link-emphasis-very-emphasis-and-code"]/code' 1
-//@ has - '//section[@id="TOC"]/ul[@class="block top-toc"]/li/a[@href="#basic-link-emphasis-very-emphasis-and-code"]/code' 'code'
+//@ has - '//section[@id="rustdoc-toc"]/h3' 'Sections'
+//@ has - '//section[@id="rustdoc-toc"]/ul[@class="block top-toc"]/li/a[@href="#basic-link-emphasis-very-emphasis-and-code"]/@title' 'Basic link, emphasis, very emphasis and `code`'
+//@ has - '//section[@id="rustdoc-toc"]/ul[@class="block top-toc"]/li/a[@href="#basic-link-emphasis-very-emphasis-and-code"]' 'Basic link, emphasis, very emphasis and code'
+//@ count - '//section[@id="rustdoc-toc"]/ul[@class="block top-toc"]/li/a[@href="#basic-link-emphasis-very-emphasis-and-code"]/em' 0
+//@ count - '//section[@id="rustdoc-toc"]/ul[@class="block top-toc"]/li/a[@href="#basic-link-emphasis-very-emphasis-and-code"]/a' 0
+//@ count - '//section[@id="rustdoc-toc"]/ul[@class="block top-toc"]/li/a[@href="#basic-link-emphasis-very-emphasis-and-code"]/code' 1
+//@ has - '//section[@id="rustdoc-toc"]/ul[@class="block top-toc"]/li/a[@href="#basic-link-emphasis-very-emphasis-and-code"]/code' 'code'
diff --git a/tests/rustdoc/sidebar/top-toc-idmap.rs b/tests/rustdoc/sidebar/top-toc-idmap.rs
index fdb99fd05a1..af07cb4179b 100644
--- a/tests/rustdoc/sidebar/top-toc-idmap.rs
+++ b/tests/rustdoc/sidebar/top-toc-idmap.rs
@@ -16,10 +16,10 @@
 
 //@ has foo/index.html
 // User header
-//@ has - '//section[@id="TOC"]/ul[@class="block top-toc"]/li/a[@href="#structs"]' 'Structs'
+//@ has - '//section[@id="rustdoc-toc"]/ul[@class="block top-toc"]/li/a[@href="#structs"]' 'Structs'
 //@ has - '//details[@class="toggle top-doc"]/div[@class="docblock"]/h2[@id="structs"]' 'Structs'
 // Built-in header
-//@ has - '//section[@id="TOC"]/ul[@class="block"]/li/a[@href="#structs-1"]' 'Structs'
+//@ has - '//section[@id="rustdoc-toc"]/ul[@class="block"]/li/a[@href="#structs-1"]' 'Structs'
 //@ has - '//section[@id="main-content"]/h2[@id="structs-1"]' 'Structs'
 
 /// # Fields
@@ -31,12 +31,12 @@
 
 //@ has foo/struct.MyStruct.html
 // User header
-//@ has - '//section[@id="TOC"]/ul[@class="block top-toc"]/li/a[@href="#fields-1"]' 'Fields'
+//@ has - '//section[@id="rustdoc-toc"]/ul[@class="block top-toc"]/li/a[@href="#fields-1"]' 'Fields'
 //@ has - '//details[@class="toggle top-doc"]/div[@class="docblock"]/h2[@id="fields-1"]' 'Fields'
 // Only one level of nesting
-//@ count - '//section[@id="TOC"]/ul[@class="block top-toc"]//a' 2
+//@ count - '//section[@id="rustdoc-toc"]/ul[@class="block top-toc"]//a' 2
 // Built-in header
-//@ has - '//section[@id="TOC"]/h3/a[@href="#fields"]' 'Fields'
+//@ has - '//section[@id="rustdoc-toc"]/h3/a[@href="#fields"]' 'Fields'
 //@ has - '//section[@id="main-content"]/h2[@id="fields"]' 'Fields'
 
 pub struct MyStruct {
diff --git a/tests/rustdoc/sidebar/top-toc-nil.rs b/tests/rustdoc/sidebar/top-toc-nil.rs
index c338bd67fcf..d72d41abf88 100644
--- a/tests/rustdoc/sidebar/top-toc-nil.rs
+++ b/tests/rustdoc/sidebar/top-toc-nil.rs
@@ -4,4 +4,4 @@
 
 //@ has foo/index.html
 // User header
-//@ !has - '//section[@id="TOC"]/ul[@class="block top-toc"]' 'Basic link and emphasis'
+//@ !has - '//section[@id="rustdoc-toc"]/ul[@class="block top-toc"]' 'Basic link and emphasis'