REAPER v6.43+dev1227

v6.43+dev1227 - December 27 2021

* Includes feature branch: render internals simplification/cleanup
* Includes feature branch: user-defined action overhaul
* Includes feature branch: media item normalization
* Includes feature branch: media explorer toolbar
* Includes feature branch: media item fixed lanes
* Includes feature branch: JSFX internals overhaul/cleanup/modernization
* Includes feature branch: Windows very long pathname support
+ Super8: fix recording glitches that could occur during looped project-synchronized playback [t=261147]
+ macOS: add per-theme option to not use themed windows when in dark-mode (enabled by default theme)
+ macOS: live FX multiprocessing threads join the CoreAudio workgroup if available
+ macOS: use THREAD_TIME_CONSTRAINT_POLICY for Live FX multiprocessing threads on Big Sur and later
# ReaScript: remove higher-level NormalizeItems(), add lower-level NormalizeItem() to calculate the normalization adjustment for a single media source
# macOS: automatically limit live FX multiprocessing threads to workgroup size
# macOS: tweak arm64 worker thread synchronization timings