diff --git a/library/core/src/option.rs b/library/core/src/option.rs
index 1e1e961369698..1c68abaf79d23 100644
--- a/library/core/src/option.rs
+++ b/library/core/src/option.rs
@@ -594,34 +594,6 @@ impl<T> Option<T> {
         }
     }
 
-    /// Inserts `value` into the option then returns a mutable reference to it.
-    ///
-    /// If the option already contains a value, the old value is dropped.
-    ///
-    /// # Example
-    ///
-    /// ```
-    /// let mut opt = None;
-    /// let val = opt.insert(1);
-    /// assert_eq!(*val, 1);
-    /// assert_eq!(opt.unwrap(), 1);
-    /// let val = opt.insert(2);
-    /// assert_eq!(*val, 2);
-    /// *val = 3;
-    /// assert_eq!(opt.unwrap(), 3);
-    /// ```
-    #[inline]
-    #[stable(feature = "option_insert", since = "1.53.0")]
-    pub fn insert(&mut self, value: T) -> &mut T {
-        *self = Some(value);
-
-        match self {
-            Some(v) => v,
-            // SAFETY: the code above just filled the option
-            None => unsafe { hint::unreachable_unchecked() },
-        }
-    }
-
     /////////////////////////////////////////////////////////////////////////
     // Iterator constructors
     /////////////////////////////////////////////////////////////////////////
@@ -849,12 +821,46 @@ impl<T> Option<T> {
     }
 
     /////////////////////////////////////////////////////////////////////////
-    // Entry-like operations to insert if None and return a reference
+    // Entry-like operations to insert a value and return a reference
     /////////////////////////////////////////////////////////////////////////
 
+    /// Inserts `value` into the option then returns a mutable reference to it.
+    ///
+    /// If the option already contains a value, the old value is dropped.
+    ///
+    /// See also [`Option::get_or_insert`], which doesn't update the value if
+    /// the option already contains [`Some`].
+    ///
+    /// # Example
+    ///
+    /// ```
+    /// let mut opt = None;
+    /// let val = opt.insert(1);
+    /// assert_eq!(*val, 1);
+    /// assert_eq!(opt.unwrap(), 1);
+    /// let val = opt.insert(2);
+    /// assert_eq!(*val, 2);
+    /// *val = 3;
+    /// assert_eq!(opt.unwrap(), 3);
+    /// ```
+    #[inline]
+    #[stable(feature = "option_insert", since = "1.53.0")]
+    pub fn insert(&mut self, value: T) -> &mut T {
+        *self = Some(value);
+
+        match self {
+            Some(v) => v,
+            // SAFETY: the code above just filled the option
+            None => unsafe { hint::unreachable_unchecked() },
+        }
+    }
+
     /// Inserts `value` into the option if it is [`None`], then
     /// returns a mutable reference to the contained value.
     ///
+    /// See also [`Option::insert`], which updates the value even if
+    /// the option already contains [`Some`].
+    ///
     /// # Examples
     ///
     /// ```
diff --git a/src/bootstrap/doc.rs b/src/bootstrap/doc.rs
index dc96fd819d558..87f8cf160e001 100644
--- a/src/bootstrap/doc.rs
+++ b/src/bootstrap/doc.rs
@@ -461,15 +461,6 @@ impl Step for Std {
         // create correct links between crates because rustdoc depends on the
         // existence of the output directories to know if it should be a local
         // or remote link.
-        //
-        // There's also a mild hack here where we build the first crate in this
-        // list, core, twice. This is currently necessary to make sure that
-        // cargo's cached rustc/rustdoc versions are up to date which means
-        // cargo won't delete the out_dir we create for the stampfile.
-        // Essentially any crate could go into the first slot here as it's
-        // output directory will be deleted by us (as cargo will purge the stamp
-        // file during the first slot's run), and core is relatively fast to
-        // build so works OK to fill this 'dummy' slot.
         let krates = ["core", "alloc", "std", "proc_macro", "test"];
         for krate in &krates {
             run_cargo_rustdoc_for(krate);
diff --git a/src/librustdoc/html/layout.rs b/src/librustdoc/html/layout.rs
index c50ebf1e6dcce..dc29add933314 100644
--- a/src/librustdoc/html/layout.rs
+++ b/src/librustdoc/html/layout.rs
@@ -68,7 +68,7 @@ crate fn render<T: Print, S: Print>(
     </style>\
 </head>\
 <body class=\"rustdoc {css_class}\">\
-    <!--[if lte IE 8]>\
+    <!--[if lte IE 11]>\
     <div class=\"warning\">\
         This old browser is unsupported and will most likely display funky \
         things.\
diff --git a/src/librustdoc/html/render/mod.rs b/src/librustdoc/html/render/mod.rs
index 7cb6466817c45..d773f37ad90a3 100644
--- a/src/librustdoc/html/render/mod.rs
+++ b/src/librustdoc/html/render/mod.rs
@@ -509,7 +509,7 @@ fn document(w: &mut Buffer, cx: &Context<'_>, item: &clean::Item, parent: Option
         info!("Documenting {}", name);
     }
     document_item_info(w, cx, item, false, parent);
-    document_full(w, item, cx, "", false);
+    document_full(w, item, cx, false);
 }
 
 /// Render md_text as markdown.
@@ -518,15 +518,13 @@ fn render_markdown(
     cx: &Context<'_>,
     md_text: &str,
     links: Vec<RenderedLink>,
-    prefix: &str,
     is_hidden: bool,
 ) {
     let mut ids = cx.id_map.borrow_mut();
     write!(
         w,
-        "<div class=\"docblock{}\">{}{}</div>",
+        "<div class=\"docblock{}\">{}</div>",
         if is_hidden { " hidden" } else { "" },
-        prefix,
         Markdown(
             md_text,
             &links,
@@ -546,12 +544,11 @@ fn document_short(
     item: &clean::Item,
     cx: &Context<'_>,
     link: AssocItemLink<'_>,
-    prefix: &str,
     is_hidden: bool,
-    parent: Option<&clean::Item>,
+    parent: &clean::Item,
     show_def_docs: bool,
 ) {
-    document_item_info(w, cx, item, is_hidden, parent);
+    document_item_info(w, cx, item, is_hidden, Some(parent));
     if !show_def_docs {
         return;
     }
@@ -570,39 +567,17 @@ fn document_short(
 
         write!(
             w,
-            "<div class='docblock{}'>{}{}</div>",
+            "<div class='docblock{}'>{}</div>",
             if is_hidden { " hidden" } else { "" },
-            prefix,
             summary_html,
         );
-    } else if !prefix.is_empty() {
-        write!(
-            w,
-            "<div class=\"docblock{}\">{}</div>",
-            if is_hidden { " hidden" } else { "" },
-            prefix
-        );
     }
 }
 
-fn document_full(
-    w: &mut Buffer,
-    item: &clean::Item,
-    cx: &Context<'_>,
-    prefix: &str,
-    is_hidden: bool,
-) {
+fn document_full(w: &mut Buffer, item: &clean::Item, cx: &Context<'_>, is_hidden: bool) {
     if let Some(s) = cx.shared.maybe_collapsed_doc_value(item) {
         debug!("Doc block: =====\n{}\n=====", s);
-        render_markdown(w, cx, &*s, item.links(cx), prefix, is_hidden);
-    } else if !prefix.is_empty() {
-        if is_hidden {
-            w.write_str("<div class=\"docblock hidden\">");
-        } else {
-            w.write_str("<div class=\"docblock\">");
-        }
-        w.write_str(prefix);
-        w.write_str("</div>");
+        render_markdown(w, cx, &s, item.links(cx), is_hidden);
     }
 }
 
@@ -1547,30 +1522,21 @@ fn render_impl(
                         // because impls can't have a stability.
                         if item.doc_value().is_some() {
                             document_item_info(w, cx, it, is_hidden, Some(parent));
-                            document_full(w, item, cx, "", is_hidden);
+                            document_full(w, item, cx, is_hidden);
                         } else {
                             // In case the item isn't documented,
                             // provide short documentation from the trait.
-                            document_short(
-                                w,
-                                it,
-                                cx,
-                                link,
-                                "",
-                                is_hidden,
-                                Some(parent),
-                                show_def_docs,
-                            );
+                            document_short(w, it, cx, link, is_hidden, parent, show_def_docs);
                         }
                     }
                 } else {
                     document_item_info(w, cx, item, is_hidden, Some(parent));
                     if show_def_docs {
-                        document_full(w, item, cx, "", is_hidden);
+                        document_full(w, item, cx, is_hidden);
                     }
                 }
             } else {
-                document_short(w, item, cx, link, "", is_hidden, Some(parent), show_def_docs);
+                document_short(w, item, cx, link, is_hidden, parent, show_def_docs);
             }
         }
     }
diff --git a/src/librustdoc/html/static/main.js b/src/librustdoc/html/static/main.js
index f017fd846b1db..be8d0a5996f9d 100644
--- a/src/librustdoc/html/static/main.js
+++ b/src/librustdoc/html/static/main.js
@@ -1281,7 +1281,7 @@ function hideThemeButtonState() {
         if (currentType) {
             currentType = currentType.getElementsByClassName("rust")[0];
             if (currentType) {
-                currentType.classList.forEach(function(item) {
+                onEachLazy(currentType.classList, function(item) {
                     if (item !== "main") {
                         className = item;
                         return true;