I searched “Off-line Help” (and alike), and the best hint, I got, is https://manual.audacityteam.org/man/unzipping_the_manual.html
But this didn’t help me.
Lately, I downloaded “audacity-win-2.3.0.zip” and “audacity-manual-2.3.0.zip”
I unzipped “audacity-win-2.3.0.zip” in a folder named audacity-win-2.3.0 and located on the lap hard drive (D:) but not on its root.
Then, I placed a shortcut of “audacity.exe” on the desktop.
I also unzipped “audacity-manual-2.3.0.zip” in a folder named “help” and place it in the same directory of “audacity.exe”.
After running “audacity.exe”, the location of the “help” folder couldn’t be detected by the program.
I wonder what I missed to do (for instance, ‘Location of Manual’ is set to ‘Local’).