diff --git a/modules/module-lua-scripting/wplua/sandbox.lua b/modules/module-lua-scripting/wplua/sandbox.lua
index 67c40009..cb49e9e5 100644
--- a/modules/module-lua-scripting/wplua/sandbox.lua
+++ b/modules/module-lua-scripting/wplua/sandbox.lua
@@ -11,72 +11,51 @@
 local SANDBOX_CONFIG = ...
 local SANDBOX_ENV = {}
 
-local function populate_env(id)
-  local module, method = id:match('([^%.]+)%.([^%.]+)')
-  if module then
-    SANDBOX_ENV[module]         = SANDBOX_ENV[module] or {}
-    SANDBOX_ENV[module][method] = _G[module][method]
-  else
-    SANDBOX_ENV[id] = _G[id]
+function create_sandbox_env()
+  local function populate_env(id)
+    local module, method = id:match('([^%.]+)%.([^%.]+)')
+    if module then
+      SANDBOX_ENV[module]         = SANDBOX_ENV[module] or {}
+      SANDBOX_ENV[module][method] = _G[module][method]
+    else
+      SANDBOX_ENV[id] = _G[id]
+    end
   end
-end
 
--- List of safe functions and packages
-if SANDBOX_CONFIG["minimal_std"] then
-  -- minimal list, used for config files
-  ([[
-    _VERSION ipairs pairs select tonumber tostring type
+  if not SANDBOX_ENV._VERSION then
+    -- List of exported functions and packages
+    ([[ _VERSION assert error ipairs   next pairs  tonumber
+        pcall    select print tostring type xpcall require
+        table    string math  package  utf8 debug  coroutine
+        os.clock  os.difftime os.time  os.date     os.getenv
+    ]]):gsub('%S+', populate_env)
 
-    table
-
-    string.byte string.char  string.find  string.format string.gmatch
-    string.gsub string.len   string.lower string.match  string.reverse
-    string.sub  string.upper
-
-  ]]):gsub('%S+', populate_env)
-else
-  -- full list, used for scripts
-  ([[
-    _VERSION assert error    ipairs   next pairs  print
-    pcall    select tonumber tostring type xpcall require
-
-    table utf8
-
-    math.abs   math.acos math.asin math.atan       math.ceil
-    math.cos   math.deg  math.exp  math.tointeger  math.floor      math.fmod
-    math.huge  math.ult  math.log  math.maxinteger math.mininteger math.max
-    math.min   math.modf math.pi   math.rad        math.random
-    math.sin   math.sqrt math.tan  math.type
-
-    string.byte string.char  string.find  string.format string.gmatch
-    string.gsub string.len   string.lower string.match  string.reverse
-    string.sub  string.upper
-
-    os.clock os.difftime os.time os.date os.getenv
-
-  ]]):gsub('%S+', populate_env)
-end
-
--- Additionally export everything in SANDBOX_EXPORT
-if type(SANDBOX_EXPORT) == "table" then
-  for k, v in pairs(SANDBOX_EXPORT) do
-    SANDBOX_ENV[k] = v
-  end
-end
-
--- Additionally protect packages from malicious scripts trying to override methods
-for k, v in pairs(SANDBOX_ENV) do
-  if type(v) == "table" then
-    SANDBOX_ENV[k] = setmetatable({}, {
-      __index = v,
-      __newindex = function(_, attr_name, _)
-        error('Can not modify ' .. k .. '.' .. attr_name .. '. Protected by the sandbox.')
+    -- Additionally export everything in SANDBOX_EXPORT
+    if type(SANDBOX_EXPORT) == "table" then
+      for k, v in pairs(SANDBOX_EXPORT) do
+        SANDBOX_ENV[k] = v
       end
-    })
-  end
-end
+    end
 
-populate_env("package")
+    -- Additionally protect packages from malicious scripts trying to override methods
+    for k, v in pairs(SANDBOX_ENV) do
+      if type(v) == "table" then
+        SANDBOX_ENV[k] = setmetatable({}, {
+          __index = v,
+          __newindex = function(_, attr_name, _)
+            error('Can not modify ' .. k .. '.' .. attr_name .. '. Protected by the sandbox.')
+          end
+        })
+      end
+    end
+  end
+
+  -- chunk's environment will be an empty table with __index
+  -- to access our SANDBOX_ENV (without being able to write it)
+  return setmetatable({}, {
+    __index = SANDBOX_ENV,
+  })
+end
 
 if SANDBOX_CONFIG["isolate_env"] then
   -- in isolate_env mode, use a separate enviornment for each loaded chunk and
@@ -84,11 +63,7 @@ if SANDBOX_CONFIG["isolate_env"] then
   SANDBOX_ENV_LIST = {}
 
   function sandbox(chunk, ...)
-    -- chunk's environment will be an empty table with __index
-    -- to access our SANDBOX_ENV (without being able to write it)
-    local env = setmetatable({}, {
-      __index = SANDBOX_ENV,
-    })
+    local env = create_sandbox_env()
     -- store the chunk's environment so that it is not garbage collected
     table.insert(SANDBOX_ENV_LIST, env)
     -- set it as the chunk's 1st upvalue (__ENV)
@@ -100,9 +75,7 @@ else
   -- in common_env mode, use the same environment for all loaded chunks
   -- chunk's environment will be an empty table with __index
   -- to access our SANDBOX_ENV (without being able to write it)
-  SANDBOX_COMMON_ENV = setmetatable({}, {
-    __index = SANDBOX_ENV,
-  })
+  SANDBOX_COMMON_ENV = create_sandbox_env()
 
   function sandbox(chunk, ...)
     -- set it as the chunk's 1st upvalue (__ENV)
diff --git a/modules/module-lua-scripting/wplua/wplua.c b/modules/module-lua-scripting/wplua/wplua.c
index 18f942f1..b33960dd 100644
--- a/modules/module-lua-scripting/wplua/wplua.c
+++ b/modules/module-lua-scripting/wplua/wplua.c
@@ -24,7 +24,7 @@ _wplua_openlibs (lua_State *L)
   static const luaL_Reg loadedlibs[] = {
     {"_G", luaopen_base},
     {LUA_LOADLIBNAME, luaopen_package},
-    /* {LUA_COLIBNAME, luaopen_coroutine}, */
+    {LUA_COLIBNAME, luaopen_coroutine},
     {LUA_TABLIBNAME, luaopen_table},
     /* {LUA_IOLIBNAME, luaopen_io}, */
     {LUA_OSLIBNAME, luaopen_os},