OT is nominally functional on a 68030 Mac with System 7.1. It works far better with at least 7.5.3, having been made part of the System software from 7.5.2 onwards. Previously it had been a separate installation, for which v1.1.2 (still downloadable) was the last. Its presence is quickly ascertained by looking at your Extensions Folder for its five elements.

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