2nd parameter must be 'undefined' rather than 'null' in receiving function
2nd parameter must be 'undefined' rather than 'null' in receiving function

LearnersGuild/Rocket.Chat,LearnersGuild/Rocket.Chat,LearnersGuild/Rocket.Chat,LearnersGuild/Rocket.Chat,LearnersGuild/echo-chat,LearnersGuild/echo-chat,LearnersGuild/echo-chat,LearnersGuild/echo-chat