Patch Package:           OTP 28.1
Git Tag:                 OTP-28.1
Date:                    2025-09-17
Trouble Report Id:       OTP-16607, OTP-19552, OTP-19619, OTP-19642,
                         OTP-19646, OTP-19647, OTP-19648, OTP-19649,
                         OTP-19651, OTP-19655, OTP-19657, OTP-19659,
                         OTP-19660, OTP-19666, OTP-19667, OTP-19669,
                         OTP-19671, OTP-19677, OTP-19681, OTP-19685,
                         OTP-19686, OTP-19688, OTP-19689, OTP-19693,
                         OTP-19694, OTP-19696, OTP-19698, OTP-19704,
                         OTP-19706, OTP-19714, OTP-19719, OTP-19721,
                         OTP-19722, OTP-19723, OTP-19724, OTP-19725,
                         OTP-19726, OTP-19727, OTP-19728, OTP-19730,
                         OTP-19731, OTP-19733, OTP-19735, OTP-19736,
                         OTP-19737, OTP-19739, OTP-19745, OTP-19749,
                         OTP-19752, OTP-19754, OTP-19756, OTP-19757,
                         OTP-19758, OTP-19759, OTP-19760
Seq num:                 ERIERL-1209, ERIERL-1231, GH-10002, GH-10020,
                         GH-10057, GH-10061, GH-10065, GH-10072,
                         GH-10077, GH-10079, GH-10097, GH-10102,
                         GH-5697, GH-5756, GH-9631, GH-9638, GH-9771,
                         GH-9816, GH-9875, GH-9901, GH-9903, GH-9972,
                         GH-9987, OTP-16608, PR-10004, PR-10009,
                         PR-10011, PR-10014, PR-10019, PR-10034,
                         PR-10046, PR-10051, PR-10066, PR-10076,
                         PR-10084, PR-10085, PR-10087, PR-10090,
                         PR-10091, PR-10093, PR-10094, PR-10104,
                         PR-10106, PR-10108, PR-10112, PR-10113,
                         PR-10120, PR-10121, PR-10140, PR-10142,
                         PR-10146, PR-10147, PR-10153, PR-9589,
                         PR-9721, PR-9796, PR-9815, PR-9832, PR-9843,
                         PR-9853, PR-9862, PR-9869, PR-9876, PR-9879,
                         PR-9896, PR-9897, PR-9898, PR-9900, PR-9906,
                         PR-9909, PR-9912, PR-9927, PR-9949, PR-9954,
                         PR-9969, PR-9976, PR-9982, PR-9990
System:                  OTP
Release:                 28
Application:             asn1-5.4.2, common_test-1.29, compiler-9.0.2,
                         crypto-5.7, debugger-6.0.3, edoc-1.4.1,
                         erl_interface-5.6.1, erts-16.1, inets-9.4.2,
                         kernel-10.4, megaco-4.8.1, mnesia-4.24.1,
                         observer-2.18.1, os_mon-2.11.1,
                         public_key-1.18.3, runtime_tools-2.3,
                         snmp-5.19.1, ssl-11.4, stdlib-7.1,
                         syntax_tools-4.0.1, tools-4.1.3, wx-2.5.2,
                         xmerl-2.1.6
Predecessor:             OTP 28.0.4

Check out the git tag OTP-28.1, and build a full OTP system including
documentation. Apply one or more applications from this build as patches to your
installation using the 'otp_patch_apply' tool. For information on install
requirements, see descriptions for each application version below.

# HIGHLIGHTS

- Added support for quantum crypto signature algorithm ML-DSA (ssl and
  public_key) and key exchange algorithm ML-KEM (ssl).

  Own Id: OTP-19552
  Application(s): public_key, ssl
  Related Id(s): PR-10004

- A User's Guide to `dbg` is now available in the documentation.

  Own Id: OTP-19655
  Application(s): runtime_tools
  Related Id(s): PR-9853

- Support for ML-DSA and ML-KEM provided by OpenSSL 3.5.

  Algorithms `mldsa44`, `mldsa65` and `mldsa87` can be passed to crypto:sign/4
  and crypto:verify/5.

  New functions crypto:encapsulate_key/2 and crypto:decapsulate_key/3 can be
  used with `mlkem512`, `mlkem768` and `mlkem1024` to safely generate and
  communicate an encapsulated shared secret.

  Own Id: OTP-19657
  Application(s): crypto
  Related Id(s): PR-9900

- TLS server now fails early for supplied PEM file issues, such as the file not
  being found.

  Own Id: OTP-19706
  Application(s): ssl
  Related Id(s): GH-9631, PR-10046

# POTENTIAL INCOMPATIBILITIES

- The internal `inet_dns_tsig` and `inet_res` modules have been fixed to TSIG
  verify the correct timestamp.

  In the process two undocumented error code atoms have been corrected to
  `notauth` and `notzone` to adhere to the DNS RFCs. Code that relied on the
  previous incorrect values may have to be corrected.

  Own Id: OTP-19756
  Application(s): kernel
  Related Id(s): PR-10146

# OTP-28.1

## Fixed Bugs and Malfunctions

- When any Erlang/OTP application has been disabled by `configure`, warnings
  from `ex_doc` when building the documentation are now disabled.

  Own Id: OTP-19646
  Related Id(s): GH-9875, PR-9876

- `./otp_build` now respects `TYPE` and `FLAVOR` to when set.

  Own Id: OTP-19677
  Related Id(s): PR-9954

- Rendering of some tables in the documentation has been improved.

  Own Id: OTP-19752
  Related Id(s): PR-10142

## Improvements and New Features

- In Efficiency Guide, the section about `setelement/3` in Common Caveats has
  been updated.

  Own Id: OTP-19749
  Related Id(s): PR-10140

# asn1-5.4.2

The asn1-5.4.2 application can be applied independently of other applications on
a full OTP 28 installation.

## Fixed Bugs and Malfunctions

- Decoding a constrained BIT STRING using JER was broken.

  Own Id: OTP-19681
  Related Id(s): PR-9949

- NIFs and linked-in drivers are now loadable when running in an Erlang source
  tree on Windows.

  Own Id: OTP-19686
  Related Id(s): PR-9969

> #### Full runtime dependencies of asn1-5.4.2
>
> erts-14.0, kernel-9.0, stdlib-5.0

# common_test-1.29

The common_test-1.29 application can be applied independently of other
applications on a full OTP 28 installation.

## Improvements and New Features

- Improved printing of maps. Map keys are now printed in the same order as
  `maps:iterator(Map, ordered)` would sort them.

  Own Id: OTP-19642
  Related Id(s): ERIERL-1231, PR-9862

- `ct:print` will now suppress printing of timestamp and heading when the
  heading option is set to the empty string.

  Own Id: OTP-19714
  Related Id(s): PR-10051

> #### Full runtime dependencies of common_test-1.29
>
> compiler-6.0, crypto-4.5, debugger-4.1, erts-7.0, ftp-1.0, inets-6.0,
> kernel-8.4, observer-2.1, runtime_tools-1.8.16, sasl-2.5, snmp-5.1.2, ssh-4.0,
> stdlib-4.0, syntax_tools-1.7, tools-3.2, xmerl-1.3.8

# compiler-9.0.2

The compiler-9.0.2 application can be applied independently of other
applications on a full OTP 28 installation.

## Fixed Bugs and Malfunctions

- Fixed a compiler crash caused by patch order in destructive update.

  Own Id: OTP-19660
  Related Id(s): GH-9903, PR-9909

- Fixed a compiler crash in `beam_ssa_pre_codegen` caused by wrong handling of
  multiple phi patches in the destructive update pass.

  Own Id: OTP-19689
  Related Id(s): GH-9987, PR-9990

- Fixed a crash when a zip generator contains a map pattern.

  Own Id: OTP-19693
  Related Id(s): GH-10002, PR-10009

- In rare circumstances, the compiler could crash when compiling code using bit
  syntax construction.

  Own Id: OTP-19722
  Related Id(s): GH-10077, PR-10090

- A few minor bugs that could affect the `beam_debug_info` option were fixed.

  Own Id: OTP-19758
  Related Id(s): PR-10153

> #### Full runtime dependencies of compiler-9.0.2
>
> crypto-5.1, erts-13.0, kernel-8.4, stdlib-6.0

# crypto-5.7

The crypto-5.7 application can be applied independently of other applications on
a full OTP 28 installation.

## Fixed Bugs and Malfunctions

- NIFs and linked-in drivers are now loadable when running in an Erlang source
  tree on Windows.

  Own Id: OTP-19686
  Related Id(s): PR-9969

- Fixed bug seen to cause beam crash when doing `init:restart()` with `crypto`
  statically linked to OpenSSL (`--disable-dynamic-ssl-lib`). Bug exists since
  OTP 28.0.

  Own Id: OTP-19721
  Related Id(s): GH-10061, PR-10076

- Fixed `crypto:strong_rand_bytes` failing after `init:restart` on MacOS with
  statically linked OpenSSL.

  Own Id: OTP-19725
  Related Id(s): GH-10079, PR-10085

- Fixed `crypto:hash(shake128 | shake256)` for OpenSSL 3.4 and newer.

  Own Id: OTP-19733
  Related Id(s): GH-9901, PR-9982

- Rendering of some tables in the documentation has been improved.

  Own Id: OTP-19752
  Related Id(s): PR-10142

## Improvements and New Features

- Support for ML-DSA and ML-KEM provided by OpenSSL 3.5.

  Algorithms `mldsa44`, `mldsa65` and `mldsa87` can be passed to crypto:sign/4
  and crypto:verify/5.

  New functions crypto:encapsulate_key/2 and crypto:decapsulate_key/3 can be
  used with `mlkem512`, `mlkem768` and `mlkem1024` to safely generate and
  communicate an encapsulated shared secret.

  Own Id: OTP-19657
  Related Id(s): PR-9900

  *** HIGHLIGHT ***

- Added support for SHA2 512/224 and SHA2 512/256 truncated hashes.

  Own Id: OTP-19666
  Related Id(s): PR-9721

> #### Full runtime dependencies of crypto-5.7
>
> erts-9.0, kernel-6.0, stdlib-3.9

# debugger-6.0.3

The debugger-6.0.3 application can be applied independently of other
applications on a full OTP 28 installation.

## Fixed Bugs and Malfunctions

- Fixed unbound error in interpreted modules

  Own Id: OTP-19719
  Related Id(s): GH-10057, PR-10066

> #### Full runtime dependencies of debugger-6.0.3
>
> compiler-8.0, erts-15.0, kernel-10.0, stdlib-7.0, wx-2.0

# edoc-1.4.1

The edoc-1.4.1 application can be applied independently of other applications on
a full OTP 28 installation.

## Fixed Bugs and Malfunctions

- Rendering of some tables in the documentation has been improved.

  Own Id: OTP-19752
  Related Id(s): PR-10142

> #### Full runtime dependencies of edoc-1.4.1
>
> erts-11.0, inets-5.10, kernel-7.0, stdlib-4.0, syntax_tools-2.0, xmerl-1.3.7

# erl_interface-5.6.1

The erl_interface-5.6.1 application can be applied independently of other
applications on a full OTP 28 installation.

## Improvements and New Features

- Fixed C compiler warnings generated by codechecker.

  Own Id: OTP-19671
  Related Id(s): PR-9832

## Known Bugs and Problems

- The `ei` API for decoding/encoding terms is not fully 64-bit compatible since
  terms that have a representation on the external term format larger than 2 GB
  cannot be handled.

  Own Id: OTP-16607
  Related Id(s): OTP-16608

# erts-16.1

The erts-16.1 application can be applied independently of other applications on
a full OTP 28 installation.

## Fixed Bugs and Malfunctions

- Made sure to not set any terminal settings when they have not been changed.
  Doing so can trigger a SIGTTOU signal which would terminate Erlang when it
  should not.

  Own Id: OTP-19685
  Related Id(s): PR-9906

- As an optimization, when the unicode:characters_to_binary/3 was used to
  convert from `latin1` to `utf8` or vice versa, it would return the original
  binary unchanged if it only contained 7-bit ASCII characters. That
  otpimization was broken in Erlang/OTP 27, and has now been mended.

  Own Id: OTP-19728
  Related Id(s): GH-10072, PR-10093

## Improvements and New Features

- Fixed C compiler warnings generated by codechecker.

  Own Id: OTP-19671
  Related Id(s): PR-9832

- Added support in module `re` for export and import of compiled regular
  expression in order to safely move them between Erlang node instances.

  Own Id: OTP-19730
  Related Id(s): PR-9976

- Added new `erl` command line flag `+Mumadtn <bool>` causing `MADV_DONTNEED` to
  be passed to `madvise()` instead of `MADV_FREE`.

  Own Id: OTP-19739
  Related Id(s): PR-10113

> #### Full runtime dependencies of erts-16.1
>
> kernel-9.0, sasl-3.3, stdlib-4.1

# inets-9.4.2

The inets-9.4.2 application can be applied independently of other applications
on a full OTP 28 installation.

## Fixed Bugs and Malfunctions

- Fixed a RFC 2616 violation, where a http request, made by httpc, without
  providing any options, would be sent with an empty TE header, without also
  having a TE value in the connection header. Now the default request doesn't
  send a TE header at all.

  Own Id: OTP-19760
  Related Id(s): GH-10065, PR-10120

> #### Full runtime dependencies of inets-9.4.2
>
> erts-14.0, kernel-9.0, mnesia-4.12, public_key-1.13, runtime_tools-1.8.14,
> ssl-9.0, stdlib-5.0, stdlib-6.0

# kernel-10.4

The kernel-10.4 application can be applied independently of other applications
on a full OTP 28 installation.

## Fixed Bugs and Malfunctions

- A remote shell can now exit by closing the input stream, without terminating
  the remote node.

  Own Id: OTP-19667
  Related Id(s): PR-9912

- The internal `inet_dns_tsig` and `inet_res` modules have been fixed to TSIG
  verify the correct timestamp.

  In the process two undocumented error code atoms have been corrected to
  `notauth` and `notzone` to adhere to the DNS RFCs. Code that relied on the
  previous incorrect values may have to be corrected.

  Own Id: OTP-19756
  Related Id(s): PR-10146

  *** POTENTIAL INCOMPATIBILITY ***

## Improvements and New Features

- The rudimentary DNS resolver `inet_res` has aqcuired 3 new functions
  inet_res:gethostbyname/4, `inet_res;getbyname/4` and
  inet_res:gethostbyaddr/3, that all take an option list argument.

  This option list can be used to override the Kernel application's resolver
  options when calling the `inet_res` function directly.

  Own Id: OTP-19737
  Related Id(s): ERIERL-1209, PR-10112

> #### Full runtime dependencies of kernel-10.4
>
> crypto-5.0, erts-15.2.5, sasl-3.0, stdlib-6.0

# megaco-4.8.1

The megaco-4.8.1 application can be applied independently of other applications
on a full OTP 28 installation.

## Fixed Bugs and Malfunctions

- Documentation improvements.

  Own Id: OTP-19669
  Related Id(s): PR-9927

- Rendering of some tables in the documentation has been improved.

  Own Id: OTP-19752
  Related Id(s): PR-10142

> #### Full runtime dependencies of megaco-4.8.1
>
> asn1-3.0, debugger-4.0, erts-12.0, et-1.5, kernel-8.0, runtime_tools-1.8.14,
> stdlib-2.5

# mnesia-4.24.1

The mnesia-4.24.1 application can be applied independently of other applications
on a full OTP 28 installation.

## Fixed Bugs and Malfunctions

- Mnesia no longer crashes when the node name is used as a table name.

  Own Id: OTP-19745
  Related Id(s): PR-10147

> #### Full runtime dependencies of mnesia-4.24.1
>
> erts-9.0, kernel-5.3, stdlib-5.0

# observer-2.18.1

The observer-2.18.1 application can be applied independently of other
applications on a full OTP 28 installation.

## Fixed Bugs and Malfunctions

- `etop` will now fully stop before returning from etop:stop/0.

  Own Id: OTP-19754
  Related Id(s): PR-9815

> #### Full runtime dependencies of observer-2.18.1
>
> erts-15.0, et-1.5, kernel-10.0, runtime_tools-2.1, stdlib-5.0, wx-2.3

# os_mon-2.11.1

The os_mon-2.11.1 application can be applied independently of other applications
on a full OTP 28 installation.

## Fixed Bugs and Malfunctions

- NIFs and linked-in drivers are now loadable when running in an Erlang source
  tree on Windows.

  Own Id: OTP-19686
  Related Id(s): PR-9969

> #### Full runtime dependencies of os_mon-2.11.1
>
> erts-14.0, kernel-9.0, sasl-4.2.1, stdlib-5.0

# public_key-1.18.3

Note! The public_key-1.18.3 application _cannot_ be applied independently of
other applications on an arbitrary OTP 28 installation.

       On a full OTP 28 installation, also the following runtime
       dependency has to be satisfied:
       -- crypto-5.7 (first satisfied in OTP 28.1)

## Fixed Bugs and Malfunctions

- NIFs and linked-in drivers are now loadable when running in an Erlang source
  tree on Windows.

  Own Id: OTP-19686
  Related Id(s): PR-9969

- Added missing reference to `SignedAttributes` so that it now works with the
  `der_encode` and `der_decode` functions.

  Own Id: OTP-19727
  Related Id(s): PR-10091

## Improvements and New Features

- Added support for quantum crypto signature algorithm ML-DSA (ssl and
  public_key) and key exchange algorithm ML-KEM (ssl).

  Own Id: OTP-19552
  Related Id(s): PR-10004

  *** HIGHLIGHT ***

> #### Full runtime dependencies of public_key-1.18.3
>
> asn1-5.0, crypto-5.7, erts-13.0, kernel-8.0, stdlib-4.0

# runtime_tools-2.3

The runtime_tools-2.3 application can be applied independently of other
applications on a full OTP 28 installation.

## Fixed Bugs and Malfunctions

- NIFs and linked-in drivers are now loadable when running in an Erlang source
  tree on Windows.

  Own Id: OTP-19686
  Related Id(s): PR-9969

## Improvements and New Features

- The default tracer is now aware that it is started by a remote shell
  (`-remsh`), in which case the traces will be sent to the remote group_leader
  to make the traces visible in the remote shell.

  Own Id: OTP-19648
  Related Id(s): PR-9589

- A User's Guide to `dbg` is now available in the documentation.

  Own Id: OTP-19655
  Related Id(s): PR-9853

  *** HIGHLIGHT ***

> #### Full runtime dependencies of runtime_tools-2.3
>
> erts-16.0, kernel-10.0, mnesia-4.12, stdlib-6.0

# snmp-5.19.1

The snmp-5.19.1 application can be applied independently of other applications
on a full OTP 28 installation.

## Fixed Bugs and Malfunctions

- Using ASN.1 generated code for decode/encode of basic types, starting with
  Counter64.

  Own Id: OTP-19619
  Related Id(s): GH-5756, PR-9869

## Improvements and New Features

- Reworked the timer handling of the (SNMP) manager start notification feature.

  Own Id: OTP-19696
  Related Id(s): PR-10014

- Added missing specs to already documented functions.

  Own Id: OTP-19723
  Related Id(s): PR-10087

> #### Full runtime dependencies of snmp-5.19.1
>
> asn1-5.4, crypto-4.6, erts-12.0, kernel-8.0, mnesia-4.12,
> runtime_tools-1.8.14, stdlib-5.0

# ssl-11.4

Note! The ssl-11.4 application _cannot_ be applied independently of other
applications on an arbitrary OTP 28 installation.

       On a full OTP 28 installation, also the following runtime
       dependencies have to be satisfied:
       -- crypto-5.7 (first satisfied in OTP 28.1)
       -- public_key-1.18.3 (first satisfied in OTP 28.1)

## Fixed Bugs and Malfunctions

- The sender side is now closed if an error occurs on the socket.

  Own Id: OTP-19694
  Related Id(s): PR-10011

- The PEM cache process no longer crashes when a configured file has been
  deleted before it could be read.

  Own Id: OTP-19698
  Related Id(s): GH-9638, PR-10019

- Corrected handling of ssl:sockname/1 for DTLS, so that it now will return
  the correct result in all situations.

  Own Id: OTP-19736
  Related Id(s): GH-10097, PR-10108

- Rendering of some tables in the documentation has been improved.

  Own Id: OTP-19752
  Related Id(s): PR-10142

## Improvements and New Features

- Added support for quantum crypto signature algorithm ML-DSA (ssl and
  public_key) and key exchange algorithm ML-KEM (ssl).

  Own Id: OTP-19552
  Related Id(s): PR-10004

  *** HIGHLIGHT ***

- Now allowing`send/2 `to buffer data when using sockets backend. Use
  'high_watermark' and 'low_watermark' to steer buffering as gen_tcp does.

  Own Id: OTP-19651
  Related Id(s): PR-9879

- Now allowing the PSK identity to be the empty string in TLS-1.2 for
  compatibility reasons. It is allowed according to the spec, although providing
  a proper value makes more sense.

  Own Id: OTP-19688
  Related Id(s): PR-9843

- TLS server now fails early for supplied PEM file issues, such as the file not
  being found.

  Own Id: OTP-19706
  Related Id(s): GH-9631, PR-10046

  *** HIGHLIGHT ***

> #### Full runtime dependencies of ssl-11.4
>
> crypto-5.7, erts-16.0, inets-5.10.7, kernel-10.3, public_key-1.18.3,
> runtime_tools-1.15.1, stdlib-7.0

# stdlib-7.1

Note! The stdlib-7.1 application _cannot_ be applied independently of other
applications on an arbitrary OTP 28 installation.

       On a full OTP 28 installation, also the following runtime
       dependency has to be satisfied:
       -- erts-16.0.3 (first satisfied in OTP 28.0.3)

## Fixed Bugs and Malfunctions

- The `save_module/1` command in the shell now saves both the locally defined
  records and the imported records using the `rr/1` command.

  Own Id: OTP-19647
  Related Id(s): GH-9816, PR-9897

- It's now possible to write `lists:map(fun is_atom/1, [])` or
  `lists:map(fun my_func/1, [])` in the shell, instead of
  `lists:map(fun erlang:is_atom/1, [])` or
  `lists:map(fun shell_default:my_func/1, [])`.

  Own Id: OTP-19649
  Related Id(s): GH-9771, PR-9898

- The shell no longer crashes when requesting to auto-complete map keys
  containing non-atoms.

  Own Id: OTP-19659
  Related Id(s): PR-9896

- A remote shell can now exit by closing the input stream, without terminating
  the remote node.

  Own Id: OTP-19667
  Related Id(s): PR-9912

- Fixed guard check for `is_record/2` in the linter.

  Own Id: OTP-19704
  Related Id(s): GH-10020, PR-10034

## Improvements and New Features

- Added a flag option `shell_hints` and function shell:hints/1. You can now
  disable the warning in the shell when a command is taking longer than 5
  seconds.

  Own Id: OTP-19759
  Related Id(s): PR-10121

> #### Full runtime dependencies of stdlib-7.1
>
> compiler-5.0, crypto-4.5, erts-16.0.3, kernel-10.0, sasl-3.0,
> syntax_tools-3.2.1

# syntax_tools-4.0.1

The syntax_tools-4.0.1 application can be applied independently of other
applications on a full OTP 28 installation.

## Fixed Bugs and Malfunctions

- Fixed zip generator crash in `annotate_bindings/1`

  Own Id: OTP-19731
  Related Id(s): GH-10102, PR-10104

> #### Full runtime dependencies of syntax_tools-4.0.1
>
> compiler-9.0, erts-16.0, kernel-10.3, stdlib-7.0

# tools-4.1.3

The tools-4.1.3 application can be applied independently of other applications
on a full OTP 28 installation.

## Improvements and New Features

- Fixed some deprecations for newer emacs versions.

  Own Id: OTP-19726
  Related Id(s): PR-10106

> #### Full runtime dependencies of tools-4.1.3
>
> compiler-8.5, erts-15.0, erts-15.0, kernel-10.0, runtime_tools-2.1, stdlib-6.0

# wx-2.5.2

The wx-2.5.2 application can be applied independently of other applications on a
full OTP 28 installation.

## Fixed Bugs and Malfunctions

- NIFs and linked-in drivers are now loadable when running in an Erlang source
  tree on Windows.

  Own Id: OTP-19686
  Related Id(s): PR-9969

- Now avoiding that wx crashes the VM when running on OTP28+ due to one of the
  new compiler hardening options.

  Own Id: OTP-19724
  Related Id(s): GH-9972, PR-10084

## Improvements and New Features

- `wx` was missing licenses that come from OpenGL documentation and wxWidgets
  documentation.

  Own Id: OTP-19735
  Related Id(s): PR-10094

> #### Full runtime dependencies of wx-2.5.2
>
> erts-12.0, kernel-8.0, stdlib-5.0

# xmerl-2.1.6

The xmerl-2.1.6 application can be applied independently of other applications
on a full OTP 28 installation.

## Fixed Bugs and Malfunctions

- Corrected the bug that comments couldn't be exported.

  `#xmlComment` elements is now exported when calling `export/3` or
  `export_simple/3` and similar functions. Top level comments will only be
  exported if one creates and export elements as a document.

  Own Id: OTP-19757
  Related Id(s): GH-5697, PR-9796

> #### Full runtime dependencies of xmerl-2.1.6
>
> erts-6.0, kernel-8.4, stdlib-2.5

# Thanks to

Alberto Sartori, Alexander Clouter, ausimian, Danil Zagoskin, dependabotbot,
Dmytro Lytovchenko, Dunya Kokoschka, Håkan Stenholm, Hans Svensson, Jan Uhlig,
Magnus Henoch, Mend Renovate, Paulo Tomé, Rodolfo Carvalho, Savvas Nicholas,
Simon Oulevay, Tomas Abrahamsson, Tom Schuster, Yaroslav Maslennikov