8.4 Release Notes
Improvements and feature changes
    Live 8.4 introduces native 64-bit support. The 64-bit version of Live allows the use of more than 4 gigabytes of RAM. This means that Live users can now work with Live Sets (including Sets using third-party plug-ins and ReWire configurations) that are much larger and more memory intensive than in the 32-bit version. The 64-bit version of Live works with PCs running Windows Vista/7/8 (64-bit) and with Intel-Macs running OS X 10.5 and up. For more information, please refer to our knowledge base: (https://www.ableton.com/articles/what-are-limitations-64-bit-version-live/).
    Improved the authorization dialog when launching Live as a Trial version.
    Improved automatic updates.
    The word size of the Live application is now shown in the splash screen.
    Live is now showing the email address of the currently authorized user account in the "About" window.

Bugfixes
    Live would not respond to time signature changes from a ReWire master.
    Fixed a bug which could prevent VST plugins stored in the OS X system library folder to show up in Live's browser.
    Fixed a bug in the 32-bit version, which could cause problems when resizing 32-Bit-Cocoa plugins.
    Under certain conditions, the playback position in audio clips was incorrect after changing clip start markers in unwarped clips and then re-enabling 'warp' (regression from 8.2.7).
    Deactivating a playing clip and then reactivating it would leave the clip in an incorrect state. The clip would look as if it is playing, although it was actually stopped.
    Fixed a problem with the Max for Live engine, which would cause Live to freeze when setting an audio buffer size smaller than 21 samples.
    Live parameters would no longer update correctly after deleting a Max for Live device which was mapped to that parameter via live.remote~.
    Mappings from Max devices to VST plugin parameters could get lost after saving an instrument rack preset and then reloading it.
    Fixed a graphical glitch in the Session- / Arrangement View amoeba after toggling views (mixer, crossfader, etc.).
    The Session View selection frame of the APC40 or Launchpad could get stuck after deleting scenes or undoing the creation of scenes.
    Under certain conditions, Live could hang when decoding MP3 files (Win only).
    Fixed a bug which could cause a "memory corruption error".
    Fixed a memory leak which could occur when previewing audio files in the Browser, using the "Complex" warp mode.
    Live could freeze when successively sending Program Change messages to a VST or AU plug-in (Mac OS X only).
    Live could freeze when using the "Insert Time" or "Insert Silence" commands.
    Live would crash when deleting a clip while recording.
    Live would crash when saving an Audio Effect Rack containing devices with certain side-chain routings.
    Live would crash when dropping MIDI Effect Rack presets onto Drum Rack pads or an Instrument Rack chain.
    Live would crash when changing the sample rate for audio interfaces with dynamically changing channel configurations (Mac OS X only).
    Live would crash when using the copy / paste time commands inside a group track.
    Live could crash under certain conditions when importing extremely long MP3 files into Live (several hours long files).
    Live could crash under certain conditions when deleting a VST plug-in from a drum rack's return chain.
    Live could crash under certain conditions when recording time signature changes.
    Live could crash under certain conditions when triggering scenes containing time signature changes.
    Live could crash under certain conditions when switching through rack chains (e.g. with the "Auto" select function) whilst renaming a device inside the chain.
    3 other rare crashes have been fixed.