fix(init): prevent loading multiple instances of ox_lib

Resolves #545.

init.lua

@@ -4,7 +4,7 @@
 ---LGPL-3.0-or-later <https://www.gnu.org/licenses/lgpl-3.0.en.html>
 
 if not _VERSION:find('5.4') then
-    error('^1Lua 5.4 must be enabled in the resource manifest!^0', 2)
+    error('Lua 5.4 must be enabled in the resource manifest!', 2)
 end
 
 local resourceName = GetCurrentResourceName()
@@ -13,6 +13,10 @@ local ox_lib = 'ox_lib'
 -- Some people have decided to load this file as part of ox_lib's fxmanifest?
 if resourceName == ox_lib then return end
 
+if lib and lib.name == ox_lib then
+    error(("Cannot load ox_lib more than once.\n\tRemove any duplicate entries from '@%s/fxmanifest.lua'"):format(resourceName))
+end
+
 local export = exports[ox_lib]
 
 if GetResourceState(ox_lib) ~= 'started' then