REAPER v6.43+dev1228

v6.43+dev1228 - December 28 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
+ Actions: if glue format supports BWF, write start offset when exploding multichannel audio to new files [t=261219]
+ JSFX: if REAPER has a .jsfx external editor configured, use for open in external editor
+ JSFX: scripts can write to #dbg_desc to write debug messages visible on main plug-in UI [t=260727]
+ Pan: fix manual entry of pan values when preference is set to display pan in dB [t=260722]
+ macOS: improve performance of Live FX multiprocessing
+ macOS: increase worker thread priority if Time Critical priority is set
# Theme tweak window: fix clipped status text [p=2510767]