Auto merge of #25836 - steveklabnik:gh25305, r=alexcrichton

Fixes #25794

Author: bors

mk/docs.mk

@@ -169,6 +169,7 @@ DOC_TARGETS += doc/not_found.html
 doc/not_found.html: $(D)/not_found.md $(HTML_DEPS) | doc/
 	@$(call E, rustdoc: $@)
 	$(Q)$(RUSTDOC) $(RUSTDOC_HTML_OPTS_NO_CSS) \
+		--markdown-no-toc \
 		--markdown-css http://doc.rust-lang.org/rust.css $<
 
 define DEF_DOC

src/doc/not_found.md

@@ -11,20 +11,20 @@ Looks like you've taken a wrong turn.
 
 Some things that might be helpful to you though:
 
-## Search
+# Search
 
 * <form action="https://duckduckgo.com/">
     <input type="text" id="site-search" name="q" size="80"></input>
     <input type="submit" value="Search DuckDuckGo">
 </form>
 * Rust doc search: <span id="core-search"></span>
 
-## Reference
+# Reference
 
 * [The Rust official site](http://rust-lang.org)
 * [The Rust reference](http://doc.rust-lang.org/reference.html)
 
-## Docs
+# Docs
 
 * [The standard library](http://doc.rust-lang.org/std/)