Audacity 3.0.4 was released on 24. Aug 2021.
Audacity 3.0.4 replaces all previous versions.
This is a hotfix release that fixes a bug with envelope points, which could multiply uncontrollably and cause Audacity to crash. In particular:
#1476: Envelope points are multiplied when using Filter Curve EQ or Graphic EQ
#1477: Filter Curve EQ will crash if there is an envelope point outside of the selection
This fix re-introduces an earlier, but way less destructive bug:
bugzilla 208 / #1500: Some effects delete Envelope Control Points, or do not move them when timeline changes
Other than that, this release is identical to Version 3.0.3.
Windows
Audacity 3.0.4 requires the CPU to support the SSE2 instruction set which should be available on any Intel hardware produced after 2001 and any AMD hardware produced after 2003.
To check what SSE levels your CPU supports, you can install CPU-Z.
If your hardware only supports SSE, you may download Audacity 2.0.6 see the Legacy Windows page on the Audacity Website.
3.0.4 does not support Windows XP.
You may try 2.2.2 on XP, but it is unsupported.
macOS / Mac OS X
Audacity 3.0.4 is for Intel Macs running OS X 10.7 and later and macOS.
There are legacy versions for older OS X at http://audacityteam.org/download/legacy-mac/.
Linux
Linux support is tested on Ubuntu Linux.
Other Linux distributions should work, but aren't tested by the Audacity team.
This page is an overview of prominent new functionality that has been introduced in Audacity 3.0.4
Version 3.0.4 is a hotfix release.
Fixed a bug with envelope points, which could multiply uncontrollably and cause Audacity to crash. In particular:
#1476: Envelope points are multiplied when using Filter Curve EQ or Graphic EQ
#1477: Filter Curve EQ will crash if there is an envelope point outside of the selection
With the release of Audacity 3.0.0 the project file structure of Audacity was changed significantly with the entire project contained in a single unified database file.
If you have already updated to any 3.x version you should already be aware of this.
But if you are updating from any earlier 2.x Audacity version please read Updating from Audacity 2.x to Audacity 3.x.
Audacity 3.x can usually open AUP files created in older 2.x.x versions of Audacity, but saving the project in 3.x will prevent it opening again in Audacity versions prior to 3.0.0.
Note that this will leave behind the old AUP file and its associated _data folder which you will probably want to delete to recover disk space.
Audacity version 3.x should be able to open projects from Audacity 1.1 onwards - but not from 1.0