Toribash 5.53b2 is now available on beta and alpha branches on Steam for Windows.
To try it out, go to Toribash properties from your Steam Library, open Betas tab and switch to the appropriate branch.

Toribash 5.53 alpha thread
Toribash 5.53 beta thread

New in this build:

• 3 and 4 player mode support in Free Play - can be toggled via Gamerules menu.
  
  
• Added customizable gui scaling - can be accessed in Graphics tab in Settings.
  This setting is primarily targeted at players with large screens (1440p and 4k panels) to keep chat and other gui elements reasonably sized.
  
  
• Added customizable joint objects opacity - can be accessed in Effects tab in Settings.
  This setting allows to control whether joint objects that replace original joints should be visible during play mode.
  
  
• Fixed bug with saving replays which would result in overwriting an existing file and added a confirmation window.
  
• Fixed bug with replays with capitalized symbols in filename not opening on Linux (Linux executables are to come later).
  
• Slightly improved Lua UIElement text drawing performance

Apparently last build wasn't actually close to release version. This should be closer.
If you spot any bugs or experience crashes (especially in 3/4 player mode), let me know.
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Update: uploaded a fix to 4-player end game crash, was result of one of the last moment changes