diff --git a/config.example.toml b/config.example.toml
index 5ef83760aed2d..15c6bc0f12376 100644
--- a/config.example.toml
+++ b/config.example.toml
@@ -16,7 +16,7 @@
 # Use different pre-set defaults than the global defaults.
 #
 # See `src/bootstrap/defaults` for more information.
-# Note that this has no default value (x.py uses the defaults in `config.toml.example`).
+# Note that this has no default value (x.py uses the defaults in `config.example.toml`).
 #profile = <none>
 
 # Keeps track of the last version of `x.py` used.
diff --git a/library/core/src/num/shells/u16.rs b/library/core/src/num/shells/u16.rs
index b203806f46005..7394977e5078a 100644
--- a/library/core/src/num/shells/u16.rs
+++ b/library/core/src/num/shells/u16.rs
@@ -1,4 +1,4 @@
-//! Redundant constants module for the [`i16` primitive type][i16].
+//! Redundant constants module for the [`u16` primitive type][u16].
 //!
 //! New code should use the associated constants directly on the primitive type.
 
diff --git a/src/librustdoc/html/static/js/main.js b/src/librustdoc/html/static/js/main.js
index 45c0360a49ea6..56ee4c1510e8f 100644
--- a/src/librustdoc/html/static/js/main.js
+++ b/src/librustdoc/html/static/js/main.js
@@ -332,13 +332,7 @@ function preLoadCss(cssUrl) {
     };
 
     function getPageId() {
-        if (window.location.hash) {
-            const tmp = window.location.hash.replace(/^#/, "");
-            if (tmp.length > 0) {
-                return tmp;
-            }
-        }
-        return null;
+        return window.location.hash.replace(/^#/, "");
     }
 
     const toggleAllDocsId = "toggle-all-docs";
@@ -707,7 +701,7 @@ function preLoadCss(cssUrl) {
         });
 
         const pageId = getPageId();
-        if (pageId !== null) {
+        if (pageId !== "") {
             expandSection(pageId);
         }
     }());
diff --git a/src/librustdoc/html/static/js/settings.js b/src/librustdoc/html/static/js/settings.js
index 1cd552e7f25b7..ebbe6c1ca9a24 100644
--- a/src/librustdoc/html/static/js/settings.js
+++ b/src/librustdoc/html/static/js/settings.js
@@ -86,12 +86,8 @@
             if (settingId === "theme") {
                 const useSystem = getSettingValue("use-system-theme");
                 if (useSystem === "true" || settingValue === null) {
-                    if (useSystem !== "false") {
-                        settingValue = "system preference";
-                    } else {
-                        // This is the default theme.
-                        settingValue = "light";
-                    }
+                    // "light" is the default theme
+                    settingValue = useSystem === "false" ? "light" : "system preference";
                 }
             }
             if (settingValue !== null && settingValue !== "null") {
diff --git a/src/librustdoc/html/static/js/storage.js b/src/librustdoc/html/static/js/storage.js
index 8d82b5b78edbb..93979a944183b 100644
--- a/src/librustdoc/html/static/js/storage.js
+++ b/src/librustdoc/html/static/js/storage.js
@@ -53,10 +53,9 @@ function removeClass(elem, className) {
  * @param {boolean}     [reversed] - Whether to iterate in reverse
  */
 function onEach(arr, func, reversed) {
-    if (arr && arr.length > 0 && func) {
+    if (arr && arr.length > 0) {
         if (reversed) {
-            const length = arr.length;
-            for (let i = length - 1; i >= 0; --i) {
+            for (let i = arr.length - 1; i >= 0; --i) {
                 if (func(arr[i])) {
                     return true;
                 }
@@ -150,26 +149,19 @@ const updateTheme = (function() {
      * … dictates that it should be.
      */
     function updateTheme() {
-        const use = (theme, saveTheme) => {
-            switchTheme(theme, saveTheme);
-        };
-
         // maybe the user has disabled the setting in the meantime!
         if (getSettingValue("use-system-theme") !== "false") {
             const lightTheme = getSettingValue("preferred-light-theme") || "light";
             const darkTheme = getSettingValue("preferred-dark-theme") || "dark";
+            updateLocalStorage("use-system-theme", "true");
 
-            if (mql.matches) {
-                use(darkTheme, true);
-            } else {
-                // prefers a light theme, or has no preference
-                use(lightTheme, true);
-            }
+            // use light theme if user prefers it, or has no preference
+            switchTheme(mql.matches ? darkTheme : lightTheme, true);
             // note: we save the theme so that it doesn't suddenly change when
             // the user disables "use-system-theme" and reloads the page or
             // navigates to another page
         } else {
-            use(getSettingValue("theme"), false);
+            switchTheme(getSettingValue("theme"), false);
         }
     }
 
diff --git a/tests/rustdoc-gui/theme-defaults.goml b/tests/rustdoc-gui/theme-defaults.goml
new file mode 100644
index 0000000000000..d5ed536b1a962
--- /dev/null
+++ b/tests/rustdoc-gui/theme-defaults.goml
@@ -0,0 +1,24 @@
+// Ensure that the theme picker always starts with the actual defaults.
+goto: "file://" + |DOC_PATH| + "/test_docs/index.html"
+click: "#settings-menu"
+wait-for: "#theme-system-preference"
+assert: "#theme-system-preference:checked"
+assert: "#preferred-light-theme-light:checked"
+assert: "#preferred-dark-theme-dark:checked"
+assert-false: "#preferred-dark-theme-ayu:checked"
+
+// Test legacy migration from old theme setup without system-preference matching.
+// See https://github.com/rust-lang/rust/pull/77809#issuecomment-707875732
+local-storage: {
+    "rustdoc-preferred-light-theme": null,
+    "rustdoc-preferred-dark-theme": null,
+    "rustdoc-use-system-theme": null,
+    "rustdoc-theme": "ayu"
+}
+goto: "file://" + |DOC_PATH| + "/test_docs/index.html"
+click: "#settings-menu"
+wait-for: "#theme-system-preference"
+assert: "#theme-system-preference:checked"
+assert: "#preferred-light-theme-light:checked"
+assert-false: "#preferred-dark-theme-dark:checked"
+assert: "#preferred-dark-theme-ayu:checked"
diff --git a/triagebot.toml b/triagebot.toml
index 2d7be7d12734a..5f4de0562f89f 100644
--- a/triagebot.toml
+++ b/triagebot.toml
@@ -470,8 +470,8 @@ cc = ["@rust-lang/style"]
 
 [mentions."Cargo.lock"]
 message = """
-These commits modify the `Cargo.lock` file. Random changes to `Cargo.lock` can be introduced when switching branches and rebasing PRs. 
-This was probably unintentional and should be reverted before this PR is merged. 
+These commits modify the `Cargo.lock` file. Random changes to `Cargo.lock` can be introduced when switching branches and rebasing PRs.
+This was probably unintentional and should be reverted before this PR is merged.
 
 If this was intentional then you can ignore this comment.
 """
@@ -499,7 +499,6 @@ compiler-team = [
 ]
 compiler-team-contributors = [
     "@compiler-errors",
-    "@eholk",
     "@jackh726",
     "@TaKO8Ki",
     "@WaffleLapkin",