Does -f bestvideo prefer vp9 over other codecs? Same question for bestaudio and opus

[ZYinMD]

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For youtube.com, I currently do this:
-f bestvideo[height<=?1080]+bestaudio/best.

On top of [height<=?1080], there are 3 more settings I want to do, but I think they're already the default? Just want to double check:

1. For vcodec, prefer vp9 over bestvideo, but only when same resolutions exist
2. For acodec, prefer opus > vorbis > bestaudio
3. When combination of vp9 + opus/vorbis are used, use .webm as container.

If they're not the default, I'd like the configure them manually. In that case, I'd hope to get some help in this thread before it's closed, because I'm not confident in the complicated selectors I wrote myself.
Thanks!

[dstftw]

1, 2. vcodec and acodec are not considered by formats sorting. What is considered is media file extension but it does not really matter since base quality metadata is checked first. Only if base quality metadata is equal then media file extension is processed and it does not prefer free formats. This can be changed with --prefer-free-formats.
3. If formats being merged are compatible the container will be the original one otherwise - mkv. vp9, opus and vorbis are compatible thus merged as webm.

[ZYinMD]

Thanks @Hrxn and @dstftw for your answers, so if I pass in -f bestvideo and --prefer-free-formats at the same time, will I get VP9 over AVC?

If no, can I manually do something like -f bestvideo[height=1080][vcodec*=VP9]+bestaudio/bestvideo[height<=?1080]+bestaudio/best ? I'm not confident in what I write.