diff --git a/src/DocTests.jl b/src/DocTests.jl
index 11f7a2d3e8c..89171944abf 100644
--- a/src/DocTests.jl
+++ b/src/DocTests.jl
@@ -8,6 +8,7 @@ using DocStringExtensions
 import ..Documenter:
     Documenter,
     Documents,
+    Expanders,
     Utilities
 
 import Markdown, REPL
@@ -64,12 +65,7 @@ function doctest(block::Markdown.Code, meta::Dict, doc::Documents.Document, page
         # Define new module or reuse an old one from this page if we have a named doctest.
         name = match(r"jldoctest[ ]?(.*)$", split(lang, ';', limit = 2)[1])[1]
         sym = isempty(name) ? gensym("doctest-") : Symbol("doctest-", name)
-        sandbox = get!(page.globals.meta, sym) do
-            newmod = Module(sym)
-            # eval(expr) is available in the REPL (i.e. Main) so we emulate that for the sandbox
-            Core.eval(newmod, :(eval(x) = Core.eval($newmod, x)))
-            newmod
-        end
+        sandbox = get!(() -> Expanders.get_new_sandbox(sym), page.globals.meta, sym)
 
         # Normalise line endings.
         block.code = replace(block.code, "\r\n" => "\n")
diff --git a/src/Expanders.jl b/src/Expanders.jl
index d66758105b0..81e0abb869d 100644
--- a/src/Expanders.jl
+++ b/src/Expanders.jl
@@ -459,7 +459,7 @@ function Selectors.runner(::Type{ExampleBlocks}, x, page, doc)
     # The sandboxed module -- either a new one or a cached one from this page.
     name = match(r"^@example[ ]?(.*)$", first(split(x.language, ';', limit = 2)))[1]
     sym  = isempty(name) ? gensym("ex-") : Symbol("ex-", name)
-    mod  = get!(page.globals.meta, sym, Module(sym))::Module
+    mod  = get!(() -> get_new_sandbox(sym), page.globals.meta, sym)
 
     # "parse" keyword arguments to example (we only need to look for continued = true)
     continued = occursin(r"continued\s*=\s*true", x.language)
@@ -529,7 +529,7 @@ function Selectors.runner(::Type{REPLBlocks}, x, page, doc)
     matched === nothing && error("invalid '@repl' syntax: $(x.language)")
     name = matched[1]
     sym  = isempty(name) ? gensym("ex-") : Symbol("ex-", name)
-    mod  = get!(page.globals.meta, sym, Module(sym))::Module
+    mod  = get!(() -> get_new_sandbox(sym), page.globals.meta, sym)
     code = split(x.code, '\n'; limit = 2)[end]
     result, out = nothing, IOBuffer()
     for (ex, str) in Utilities.parseblock(x.code, doc, page)
@@ -633,4 +633,13 @@ function prepend_prompt(input)
     rstrip(String(take!(out)))
 end
 
+function get_new_sandbox(name::Symbol)
+    m = Module(name)
+    # eval(expr) is available in the REPL (i.e. Main) so we emulate that for the sandbox
+    Core.eval(m, :(eval(x) = Core.eval($m, x)))
+    # modules created with Module() does not have include defined
+    Core.eval(m, :(include(x) = Base.include($m, x)))
+    return m
+end
+
 end