directories should not be loaded

data/core/init.lua

@@ -625,6 +625,8 @@ function core.load_plugins()
     local plugin_dir = root_dir .. "/plugins"
     local files = system.list_dir(plugin_dir)
     for _, filename in ipairs(files or {}) do
+      local info = system.get_file_info(filename)
+      if info ~= nil and info.type == "file" then
         local basename = filename:match("(.-)%.lua$") or filename
         local version_match = check_plugin_version(plugin_dir .. '/' .. filename)
         if not version_match then
@@ -642,6 +644,7 @@ function core.load_plugins()
         end
       end
     end
+  end
   return no_errors, refused_list
 end