Index: head/www/firefox/pkg-message
===================================================================
--- head/www/firefox/pkg-message	(revision 546072)
+++ head/www/firefox/pkg-message	(revision 546073)
@@ -1,43 +1,48 @@
 [
 { type: install
   message: <<EOM
 ## Missing features
 
 Some features found on Windows, macOS and Linux are not implemented:
 
 - Native audio (requires OSS backend, feature parity with ALSA or PulseAudio)
 - Encrypted Media Extensions (requires Widevine CDM binary)
 - Process sandboxing (requires Capsicum backend)
 - Reduced memory usage (requires mozjemalloc)
 - Crash Reporter (requires Google Breakpad and reproducible builds)
 - Performance profiling (requires GeckoProfiler)
 - Gamepad API (requires libusbhid backend)
 - WebVR (requires open source runtime)
 - TCP fast open
 - `about:networking` (requires link state notification)
 
 ## Audio backend
 
-To select non-default audio backend open `about:config` page and
-create `media.cubeb.backend` preference. Supported values are: `alsa`,
-`jack`, `oss`, `pulse`, `pulse-rust`, `sndio`. Currently used backend can be
-inspected on `about:support` page.
+Currently used audio backend can be inspected on `about:support` page.
+Supported backends and default probing order is as follows:
+- `pulse-rust` if `pulseaudio` package is installed (PULSEAUDIO option)
+- `jack` if `jackit` package is installed (JACK option)
+- `sndio` if `sndio` package is installed (SNDIO option)
+- `alsa` if `alsa-lib` package is installed (ALSA option)
+- `oss` (always available)
+To force a specific backend open `about:config` page and create
+`media.cubeb.backend` preference.
 
 Microphone selection only works in `oss`, `pulse`, `pulse-rust` backends.
 Other backends are limited to `default` which is usually `/dev/dsp`,
 so use virtual_oss to reroute microphones from non-default devices.
 
 ## smb:// issues
 Network group, machine, and share browsing does not work correctly.
 
 ## sftp://
 Only sftp access using public key authentication works. To easily
 setup public key authentication to `remote_host`:
 
     $ ssh-keygen
     $ cat ~/.ssh/id_rsa.pub | ssh remote_host "cat >> .ssh/authorized_keys"
 
 The SSH server on `remote_host` must allow pub key authentication.
 EOM
 }
 ]
Index: head/www/firefox-esr/pkg-message
===================================================================
--- head/www/firefox-esr/pkg-message	(revision 546072)
+++ head/www/firefox-esr/pkg-message	(revision 546073)
@@ -1,43 +1,48 @@
 [
 { type: install
   message: <<EOM
 ## Missing features
 
 Some features found on Windows, macOS and Linux are not implemented:
 
 - Native audio (requires OSS backend, feature parity with ALSA or PulseAudio)
 - Encrypted Media Extensions (requires Widevine CDM binary)
 - Process sandboxing (requires Capsicum backend)
 - Reduced memory usage (requires mozjemalloc)
 - Crash Reporter (requires Google Breakpad and reproducible builds)
 - Performance profiling (requires GeckoProfiler)
 - Gamepad API (requires libusbhid backend)
 - WebVR (requires open source runtime)
 - TCP fast open
 - `about:networking` (requires link state notification)
 
 ## Audio backend
 
-To select non-default audio backend open `about:config` page and
-create `media.cubeb.backend` preference. Supported values are: `alsa`,
-`jack`, `oss`, `pulse`, `pulse-rust`, `sndio`. Currently used backend can be
-inspected on `about:support` page.
+Currently used audio backend can be inspected on `about:support` page.
+Supported backends and default probing order is as follows:
+- `pulse-rust` if `pulseaudio` package is installed (PULSEAUDIO option)
+- `jack` if `jackit` package is installed (JACK option)
+- `sndio` if `sndio` package is installed (SNDIO option)
+- `alsa` if `alsa-lib` package is installed (ALSA option)
+- `oss` (always available)
+To force a specific backend open `about:config` page and create
+`media.cubeb.backend` preference.
 
 Microphone selection only works in `oss`, `pulse`, `pulse-rust` backends.
 Other backends are limited to `default` which is usually `/dev/dsp`,
 so use virtual_oss to reroute microphones from non-default devices.
 
 ## smb:// issues
 Network group, machine, and share browsing does not work correctly.
 
 ## sftp://
 Only sftp access using public key authentication works. To easily
 setup public key authentication to `remote_host`:
 
     $ ssh-keygen
     $ cat ~/.ssh/id_rsa.pub | ssh remote_host "cat >> .ssh/authorized_keys"
 
 The SSH server on `remote_host` must allow pub key authentication.
 EOM
 }
 ]