I am impressed
 

Here what I found in Live Slackware Edition (Xfce stripped version)
I am impressed. In nowadays static build whoa, and great thanks for alsa support in firefox build. All credits go to AlienBob, whoa, standing ovation.

You are kidding, right?

For your information, the file /usr/bin/firefox is a (wrapper) shell script.

Of course it's not a dynamic executable.

Of course how stupid I am. But what about support for alsa only? So far it is only version of firefox with sound on non-pulse system. I was expecting to see something difference in ldd for this firefox. Hate pulse-s.

If you're running one that doesn't support alsa directly (such as the official mozilla binary build), then 'apulse' works nicely.

Well everything is fine
on AlienBob Liveslak. See no pa running. But I am happy to listen to Tycho on youtube. On MX Linux, Porteous - there is no sound in firefox without pulseaudio. On MX Linux forum I found that they use upstream Debian build - and supposedly Debian build does not have direct alsa support. In case of Porteous - it is less clear. Firefox on Porteous without pa has no sound. Now - guys claim Porteous is on top of Slackware. So or Slackware default firefox build lacks alsa support - or Porteous is using custom firefox build - which means it is not quite on top of Slackware. In former case firefox in Liveslak is AlienBob custom build. Complicated. But I really greatly appreciate that I can use firefox on alsa only system. This saves a lot of money - in other case I would have to spend them to buy good audio system - to cover poor pa quality.

FYI, igadoter, pulse is not an audio server. It has no means to interact with audio hardware. It still uses ALSA for that. PA is just a "conductor" for the "symphony" of options and connections. In that it creates considerable latency which really does not affect Playback, only Recording. I Record and Edit so I don't like PA either but it's easy to configure it to "go sit in a corner" even without PipeWire. PipeWire can essentially do all that at low latency and fool apps like Firefox to think PA is being used.

None of them have saved me money, not even ALSA, since I buy audiophile (not to be confused with "audiophool") gear. It would cost around $5000.00 USD to replace my PC audio gear that began 25 years ago... LONG before PA ever existed.

Sorry enorbet, you are not right. If someone has very good audio, or even good audio - there is no difference between PA and pure alsa. But for middle ware one can hear difference - in pa drums and cymbals sound like poured sand. The sound is flat. Someone posted pa was never created with audio quality in mind. Just magical word: server. But even arts (?) KDE 3.5 sound server was better in terms of sound quality. For people who create audio application - pa was a savior from alsa - say audacious still has problems with alsa only audio - but for price of sound quality. And of course pa was forced by the same side of force which pushes now pipewire. Say firefox with support for alsa, pa and pipewire?

You could be right, igadoter, but I don't see how. How does PA have any effect on playback quality? It doesn't control the hardware. It only controls ALSA AFAIK. Actaully that's what pisses me off about Firefox.

I understand why they would prefer to take the easy way out by dropping any concern for what is underneath and only deal with what is above, but the option for ALSA is still there, just disabled! Why would they bother to disable it? Of what value is it to Mozilla? Seems like a mere washing of hands to me, with no concern for those who prefer a more direct approach.

Nevertheless if using PA on "middleware" is somehow reduced quality for you, it seems likely to me you haven't setup ALSA correctly with a solid User .asoundrc.

Also, what do you consider Middleware? Onboard? Personally I consider any onboard audio chipset as substandard if only for the degradation due to noise floor. I see numerous PCI and PCIe semi-pro quality soundcards, new and used, for $30-$100 on sites like eBay. If you prefer external, some decent ones are in similar price ranges. The hardware will make WAY more difference than the software.

You need to run ldd on the binary of Firefox, which is located in /usr/lib64/firefox/firefox

However, I hate to break it to you, but even Mozilla's official binaries don't show pulse as a shared library, but it's compiled without alsa support.

Package was created using ruario's latest-firefox.sh script (mozilla-firefox-83.0-x86_64-1ro -- yes, I'm out of date, but Firefox is not my primary browser).

As has been said on other threads, this must be unique to your hardware. I noticed no difference when I moved my htpc from 14.1 to 14.2 (and to -current). I don't use passthrough (although, I did test passthrough and it sounds the same). My htpc is plugged into a relatively high-end Onkyo receiver via HDMI for video and audio. Sounds are all clear and crisp. Explosions are never muddled (and they will shake my house if I have the system turned up loud enough).

Honestly, for me the PipeWire sounds better than PulseAudio - more clear, but I do not know why.

This is what I try to understand. For sure I don't run now pa - but I can listen to music in youtube - but so far only in firefox on AlienBob Liveslak. I know ldd output - I did it - in hope I will find a clue why do I have sound in firefox on alsa? Maybe this will help
I am curious about RDD Process(?)

Research & Development Daemon?

Have you got anything selected under "Firefox Data Collection and Use" in the "Privacy and Security" page of Firefox's "Preferences"?

I just noticed that this firefox does not forks, on my stationary system ps for firefox usually looks like
these are not necessary true forks - but nonetheless - but on my output above there are only Web Content subprocesses. And mysterious RDD.

I didn't touch anything there - firefox reports standard - but perhaps one of extensions I use may spawn RDD process - https everywhere, noscript, ublock origin, privacy badger - I use them to kill google adds on youtube. I like to enjoy non-stop music.