Mathcad 15.0 M050 (the final maintenance release) officially supports:
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That night, Evan shut down the workstation and placed the dongle back into a small metal box labeled "Legacy — do not discard." It wasn't about clinging to old software; it was about preserving a chain of reasoning. The cloud could store repositories and continuous integration, but there was a kind of map in those dated files — a map that showed not only what worked, but how someone had thought through the problem. Mathcad 15