* Do not jump to location $FC0002 -- the start of the ROM under
    1.3 -- as part of performing a system RESET.  The 2.04 Kickstart
    ROM has a temporary compatibility hack called "Kickety-Split" which
    is a redirecting jump at $FC0002.  This hack does not appear on the
    A3000 ROM and due to space considerations will not appear on future
    machines.

  * Everything has moved.

  * The Supervisor stack is not in the same place as it was under 1.3.
    This has caused problems for some games that completely take over the
    Amiga.  If your program goes into Supervisor mode, you must either
    respect allocated memory or provide your own Supervisor stack when
    taking over the machine.

  * ExecBase is moved to expansion memory if possible.  Before, ExecBase
    would only end up in one of two fixed locations.  Now, ColdCapture
    may be called after expansion memory has been configured.

  * Exception/Interrupt vectors may move.  This means the 68010 and above
    Vector Base Register (VBR) may contain a non-zero value.  Poking
    assumed low memory vector addresses may have no effect.  You must
    read the VBR on 68010 and above to find the base.

  * No longer tolerant of wild Forbid() counts.  Under 1.3, sometimes
    this bug could go unnoticed.  Make sure that all Forbid()s are
    matched with one and only one Permit() (and vice versa).

  * When an Exec device gets an IORequest, it must validate io_Command.
    If the io_Command is 0 or out of range, the device must return
    IOERR_NOCMD and take no other action.  The filesystem now sends new
    commands and expects older devices to properly ignore them.

  * A fix to task-switching in Release 2 allows a busy task to properly
    regain the processor after an interrupt until either its quantum (4
    vertical blanks) is up or a higher priority task preempts it.  This
    can dramatically change the behavior of multitask programs where one
    task busyloops while another same-priority task Wait()s.  See
    "Task Switching" in the "Additional Information" section below.

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