I was transfering shield strength to the forward shields when I got this crash. 100% reproduceable.
Assert: xfer_amount >= 0
File: c:\fs2_open\code\hud\hudshield.cpp
Line: 951
[This filename points to the location of a file on the computer that built this executable]

Call stack:
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    button_function_critical()    button_function()    button_info_do()    game_process_keys()    game_frame()    game_do_frame()    game_do_state()    gameseq_process_events()    WinMainSub()    WinMain()    WinMainCRTStartup()    kernel32.dll 7c816d4f()
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