Settings for recording from a playing Youtube

Somebody must have run into this before but I don’t see the topic, so here goes.
I know that in most cases anyone can convert Youtube audio to an mp3 (or lots of other things).
However, the Youtube converters I’ve explored won’t touch anything more than one hour.
I need the audio from a 2+ hour Youtube to prepare it for a canned radio broadcast.
(I can’t just play the Youtube in the studio, because the studio is closed. A robot runs the broadcast from mp3s.)
Therefore I tried to set up to record the Youtube as it plays.
I’ve actually done this before!
Evidently I forgot the settings needed. None of the settings I’ve tried will do it.
I seek the settings.

Sometimes you can use the machines built-in services and tools. Sometimes you have to install special software.

In general you have to use software that redirects sound from playback (from the internet) to record (in Audacity). This can have unstable outcomes such as discovering the “Bong” computer warnings are being recorded, or your pickled macadamia takeout order got recorded because your built-in microphone turned on.

Windows 7…??