Lossless audio trim with FFMPEG

When dealing with lossy audio, you really don't want to re-encode it to isolate sections. Enter FFMPEG:

ffmpeg -y -i youtube-audio-file.webm -ss 00:31:26.0 -t 00:00:27.0 -c:a copy useable-file.opus

ss is the starting time. t is the duration of the section you are capturing.