Question of availability of emulator of earlier version of Ubuntu

[Bret Busby]

Hello.

An emulator; wine, is available for emulating (maybe only earlier
version(s) of) MS Windows, to provide for running applications that
run on only MS Windows, to run on Linux.

My wife has a computer that has Ubuntu 12.04 installed on it.

She will not upgrade the operating system, because she has an
application on it, that runs on 12.04, and not on later versions.

So, I am wondering whether an emulator is available, for 20.04, or,
better, for 21.04, that will emulate 12.04, to allow applications that
will not run on versions later than 12.04, to run on it.

Thank you in anticipation.

-- 
Bret Busby
Armadale
West Australia
(UTC+0800)
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