user if the "From" user is not a valid account.

not known.

That is, if any of the following text.dat entries are set to a blank/emtpy
string (by editing ctrl/text.dat or via run-time script modification), the
question will not be asked of the user allowing greater sysop-customization
of hard-coded processes (e.g. new user application):
ClearUploadQueueQ
ClearDownloadQueueQ
HangUpAfterXferQ
ChatWithGuruInsteadQ
ForwardMailQ
DownloadBatchQ
LogOffQ
DeleteErrorLogQ
ClearErrCounter
DeleteGuruLogQ
AutoTerminalQ
AnsiTerminalQ
ColorTerminalQ
ExAsciiTerminalQ
CallingFromNorthAmericaQ
ReadYourMailNowQ
NScanAllGrpsQ
SScanAllGrpsQ
NewPasswordQ
ContinueQ
EnterYourPhoneNumber
UserInfoCorrectQ
UseExternalEditorQ
DownloadAttachedFileQ
AddSubToNewScanQ (new)
RemoveFromNewScanQ
DisplaySubjectsOnlyQ
Post
SearchExtendedQ
ViewSysInfoFileQ
ViewLogonMsgQ
WithLineNumbersQ

Reading Mail prompt with multiple undeleted mails remaining, instead make
(K)ill All Mail command available, which can be still be reversed before
quitting the reading mail prompt.

inserting (long) typedefs to prevent warnings, but in the case of the JS File()
class, actually supporting file lengths > 32-bit.

Don't prompt for "delete mail from everyone" when there is only one e-mail
waiting for the user.
Use some existing text.dat entries (some old and some recently added) where
identical static strings were still being used for no apparent reason.
Added several text.dat entries for the QWK settings menu, node status, and
some other single-line messages (replacing static strings).

Added HOST and IP keywords to allow restricted access/privileges to/for
specific remote hostnames or IP addresses (wildcards allowed).
All string-argument type ARS keywords (e.g. SHELL, PROT, etc.) now support .can
style wildcards.
The current remote client is now used for protocol, host, and IP ARS checking,
when available, so this requires passing the client pointer around (which
explains why so many files are touched by this change) and takes care of a
long standing to-do item (the user's 'modem' value was used for the PROT
value checking, which was not always correct).

(non-deleted) mail in the mailbox, prompt the user to delete all the mail
waiting.

set.

Remove time32str()

send the reply to the reply-to address (by default) instead of the FROM
address.

records (using smb_putmsg) - keeps the index file from being truncated during
the operation (nightly purging of deleted message indexes?) causing corruption.

(for Unix file system compatibilty).

loadmail() change which had a trickle-up effect to the higher level functions
that use loadmail().

is rewritten (soonish)

so configured in SCFG->System->New User Values->Question Toggles.

and net_addr() to smb_netaddr().

etc).

if text/menu/*prot.asc does not exist.