In Act II: Enter the Manatee, after Guybrush returns to Mêlée Island he finds out that Ozzie Mandrill has acquired the Scumm Bar and has turned it into the Lua Bar.

This is a reference to how the previous three installments used the SCUMM scripting language, which the Bar was first named after, and how Escape from Monkey Island was the first to use the Lua programming language instead.
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