feedmail-last-chance-hook

feedmail-last-chance-hook is a variable defined in `feedmail.el'.
Its value is

nil

• This variable may be risky if used as a file-local variable.

Documentation:
User's last opportunity to modify the message on its way out.
When this hook runs, the current buffer is already the appropriate
buffer. It has already had all the header prepping from the standard
package. The next step after running the hook will be to save the
message via FCC: processing. The hook might be interested in these:
(1) `feedmail-prepped-text-buffer' contains the header and body of the
message, ready to go; (2) `feedmail-address-list' contains a list
of simplified recipients of addresses which are to be given to the
subprocess (the hook may change the list); (3) `feedmail-error-buffer'
is an empty buffer intended to soak up errors for display to the user.
If the hook allows interactive activity, the user should not send more
mail while in the hook since some of the internal buffers will be
reused and things will get confused. It's not necessary to
arrange for the undoing of any changes you make to the buffer.

You can customize this variable.