If a new message alert bounced to a staff member and the postmaster sent
back a bounce notice, which was threaded, then the agent might receive
another new message alert, which would continue a bounce loop.

include @greezybacon suggestion on fix

Fixes #2350 in `develop`

This change handles write and read error in case of decoding to temp file, and falls back to in-memory decoding in case of failure

When decoding attached files, passing the whole content of the file to imap_base64 or base64_decode leads to allocating the memory for the whole base 64 decoded file while the binary content of the file is still in memory. This leads easily to Out of memory error on limited resources servers. Using .stream_filter_append to decode the file while writing it in a temporary file uses much less memory. The content of the decoded file is then simply read from the file

When saving an attached file in the database, Passing the whole content of the file to bin2hex leads to allocating the memory for the whole hex encoded file while the binary content of the file is still in memory. This leads easily to Out of memory error on limited resources servers. Calling bin2hex on each chunk of the file greatly limits the memory usage.

Fixes #2410

This patch drops the content after the last boundary in a multi-part message
which prevents it from being considered in some case where the available
content sections are not favorable.

Backport me to v1.9

This reverts commit c4ace2d5.

If a user is created with an empty domain name (e.g. <user@>), then the user
would be associated with the first organization without a main domain
specified.

This patch ensures that the domain is not empty when making a match with an
organization.

This fixes an issue where, when the mailfetch subsystem fetches more than
one email and one of them has a TNEF attachment; each message body after the
TNEF message will use the TNEF message body.

This patch fixes the issue by clearing the TNEF body in each cycle through
the message fetching and parsing loop.

This patch automatically configures reindexing of the search table when the
table is dropped and recreated.

The DomDocument::saveHtml() method will properly urlencode() values in the
a[@href] attributes when saving. This patch allows for the sanitization
while also allowing the variable replacement system to work properly with
the sanitized values.

When using the php mail() function, the To: header encoded in the Mail_mime
library was not properly transferred to the $to variable passed to the mail
backend. The mail() function will add its own To: header which will
mimic the received destination address.

This patch ensures that the $to parameter is properly encoded.

When using call_user_func_array arguments should be passed by reference in order to allow callable receive them by reference (only defining callable to receive data by reference is not enough).

This patch will help ensure that if a ticket is not reopened on a message
(perhaps because of a out-of-office auto-reply from an enduser), then the
closing agent on a closed ticket should not be cleared.

This fixes an issue where text scrubbed with the new balancing system would
receive a leading ' <div>' if the text started with a leading whitespace.

Thanks, @torohill

This fixes a strange issue where the first field of a custom form stapled to
a ticket is not populated with data sourced from the API.

9ae01bf2 turned off HTML balancing, however,
quoted response removal will create unbalanced HTML. That HTML will be
stored unbalanced and will require extra processing when displayed on the
ticket thread.

This patch adds balancing support using libxml if enabled, which will
balance HTML without corrupting the HTML like htmLawed will with balancing
enabled.

* Reindexing did not properly flush the last batch of items to the search
  therefore reindexing would always miss the last few items.
* Creating a new html thread entry with inline images resulted in empty
  search content
* HTML tag stripping in HtmlThreadBody::getSearchable() would result in
  missing white space between some words, resulting in poor searchable
  content

Which seems to be used by recent versions of Andriod OS. It appears to be a
synonym of `multipart/related`

Also, fix roundtrip encryption if the form name changes (which is based on a
user's session), and avoid saving a NULL value if the password is not
changed when a form is updated.

If navigating back to the ticket queue (after closing a ticket, for
instance), return to the queue previously viewed.