DISPATCH M. Borins Internet-Draft M. Bynens Updates: 4329 (if approved) Google Intended status: Informational M. Miller Expires: May 3, 2020 Mozilla B. Farias October 31, 2019 ECMAScript Media Types Updates draft-ietf-dispatch-javascript-mjs-05 Abstract This document proposes updates to the ECMAScript media types, superseding the existing registrations for "application/javascript" and "text/javascript" by adding an additional extension and removing usage warnings. This document updates RFC4329, "Scripting Media Types". Status of This Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at https://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." This Internet-Draft will expire on May 3, 2020. Copyright Notice Copyright (c) 2019 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must Borins, et al. Expires May 3, 2020 [Page 1] Internet-Draft ECMAScript Media Types Updates October 2019 include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 2. Background . . . . . . . . . . . . . . . . . . . . . . . . . 2 3. Security Considerations . . . . . . . . . . . . . . . . . . . 3 4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 3 4.1. Common Javascript Media Types . . . . . . . . . . . . . . 4 4.1.1. text/javascript . . . . . . . . . . . . . . . . . . . 4 4.2. Historic Javascript Media Types . . . . . . . . . . . . . 5 4.2.1. application/ecmascript . . . . . . . . . . . . . . . 5 4.2.2. application/javascript . . . . . . . . . . . . . . . 6 4.2.3. application/x-ecmascript . . . . . . . . . . . . . . 7 4.2.4. application/x-javascript . . . . . . . . . . . . . . 8 4.2.5. text/ecmascript . . . . . . . . . . . . . . . . . . . 9 4.2.6. text/javascript1.0 . . . . . . . . . . . . . . . . . 10 4.2.7. text/javascript1.1 . . . . . . . . . . . . . . . . . 11 4.2.8. text/javascript1.2 . . . . . . . . . . . . . . . . . 12 4.2.9. text/javascript1.3 . . . . . . . . . . . . . . . . . 13 4.2.10. text/javascript1.4 . . . . . . . . . . . . . . . . . 14 4.2.11. text/javascript1.5 . . . . . . . . . . . . . . . . . 15 4.2.12. text/jscript . . . . . . . . . . . . . . . . . . . . 16 4.2.13. text/livescript . . . . . . . . . . . . . . . . . . . 17 4.2.14. text/x-ecmascript . . . . . . . . . . . . . . . . . . 18 4.2.15. text/x-javascript . . . . . . . . . . . . . . . . . . 19 5. References . . . . . . . . . . . . . . . . . . . . . . . . . 20 5.1. Normative References . . . . . . . . . . . . . . . . . . 20 5.2. Informative References . . . . . . . . . . . . . . . . . 20 Appendix A. Acknowledgements . . . . . . . . . . . . . . . . . . 20 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 20 1. Introduction This document updates the existing media types for the ECMAScript programming language. It supersedes the media types registrations in [RFC4329] for "application/javascript" and "text/javascript". 2. Background In order to formalize support for modular programs, [ECMA-262] (starting with 6th Edition) defines two top-level goal symbols (or roots to the abstract syntax tree) for the ECMAScript grammar: Module and Script. The Script goal represents the more stand-alone structure where the code executes in the global scope, while the Borins, et al. Expires May 3, 2020 [Page 2] Internet-Draft ECMAScript Media Types Updates October 2019 Module goal represents the module system built into ECMAScript starting with 6th Edition. This separation means that (in the absence of additional information) there are two possible interpretations for any given ECMAScript Source Text. The TC39 standards body for ECMAScript has determined that media types are outside of their scope of work [TC39-MIME-ISSUE]. It is not possible to fully determine if a Source Text of ECMAScript is meant to be parsed in the Module or Script grammar goals based upon content alone. Therefore, scripting environments must use out of band information in order to determine what goal a Source Text should be treated as. To this end some scripting environments have chosen to adopt a new file extension of .mjs for determining the goal of a given Source Text. 3. Security Considerations Module scripts in ECMAScript can request the fetching and processing of additional scripts, called importing. Implementations that support modules need to ensure these scripts are processed the same as scripts processed directly. Further, there may be additional privacy and security concerns depending on the location(s) the original script and its imported modules are obtained from. For instance, a scripted obtained from "host-a.example" could request to import a script from "host-b.example", which could expose information about the executing environment (e.g., IP address) to "host- b.example". With the addition of SharedArrayBuffer objects in ECMAScript version 8, it may be possible to implement a high-resolution timer which could lead to certain types of timing and side-channel attacks (e.g., [SPECTRE]). Implementations may wish to take steps to mitigate this concern, such as disabling or removing support for SharedArrayBuffer objects, or take additional steps to ensure access to this shared memory is only accessible between execution contexts that have some form of mutual trust. All other security considerations from [RFC4329] still apply. 4. IANA Considerations The media type registrations herein are divided into two major categories: the sole media type "text/javascript" which is now in common usage, and all of the media types that are obsolete. Borins, et al. Expires May 3, 2020 [Page 3] Internet-Draft ECMAScript Media Types Updates October 2019 For both categories, The ECMAScript media types are to be updated to point to a non-vendor specific standard undated specification of ECMAScript. In addition, a new file extension of .mjs is to be added to the list of file extensions with the restriction that it must correspond to the Module grammar of [ECMA-262]. Finally, the [HTML] specification uses "text/javascript" as the default media type of ECMAScript when preparing script tags; therefore, "text/javascript" intended usage is to be moved from OBSOLETE to COMMON. 4.1. Common Javascript Media Types 4.1.1. text/javascript Type name: text Subtype name: javascript Required parameters: none Optional parameters: charset, see section 4.1 of [RFC4329]. Encoding considerations: Encoding is host dependent with differences in byte order marks, the charset parameter, and text preprocessing. Security considerations: See section 5 of [RFC4329]. Interoperability considerations: See notes in various sections of [RFC4329]. Published specification: [[RFCXXXX]] Applications which use this media type: Script interpreters as discussed in [RFC4329]. Additional information: Magic number(s): n/a File extension(s): .js, .mjs Macintosh File Type Code(s): TEXT Person & email address to contact for further information: See Author's Address section. Intended usage: COMMON Borins, et al. Expires May 3, 2020 [Page 4] Internet-Draft ECMAScript Media Types Updates October 2019 Restrictions on usage: The .mjs file extension signals that the file represents a JavaScript module. Execution environments that rely on file extensions to determine how to process inputs parse .mjs files using the Module grammar of [ECMA-262]. Author: See Author's Address section. Change controller: IESG 4.2. Historic Javascript Media Types The following media types are added or updated for historical purposes. All herein have an intended usage of OBSOLETE, and are not expected to be in use with modern implementations. 4.2.1. application/ecmascript Type name: application Subtype name: ecmascript Required parameters: none Optional parameters: charset, see section 4.1 of [RFC4329]. Encoding considerations: Encoding is host dependent with differences in byte order marks, the charset parameter, and text preprocessing. Security considerations: See section 5 of [RFC4329]. Interoperability considerations: See notes in various sections of [RFC4329]. Published specification: [[RFCXXXX]] Applications which use this media type: Script interpreters as discussed in [RFC4329]. Additional information: Magic number(s): n/a File extension(s): .es, .mjs Macintosh File Type Code(s): TEXT Borins, et al. Expires May 3, 2020 [Page 5] Internet-Draft ECMAScript Media Types Updates October 2019 Person & email address to contact for further information: See Author's Address section. Intended usage: OBSOLETE Restrictions on usage: This media type is obsolete; current implementations should use text/javascript as the only JavaScript/ ECMAScript media type. The .mjs file extension signals that the file represents a JavaScript module. Execution environments that rely on file extensions to determine how to process inputs parse .mjs files using the Module grammar of [ECMA-262]. Author: See Author's Address section. Change controller: IESG 4.2.2. application/javascript Type name: application Subtype name: javascript Required parameters: none Optional parameters: charset, see section 4.1 of [RFC4329]. Encoding considerations: Encoding is host dependent with differences in byte order marks, the charset parameter, and text preprocessing. Security considerations: See section 5 of [RFC4329]. Interoperability considerations: See notes in various sections of [RFC4329]. Published specification: [[RFCXXXX]] Applications which use this media type: Script interpreters as discussed in [RFC4329]. Additional information: Magic number(s): n/a File extension(s): .js, .mjs Macintosh File Type Code(s): TEXT Borins, et al. Expires May 3, 2020 [Page 6] Internet-Draft ECMAScript Media Types Updates October 2019 Person & email address to contact for further information: See Author's Address section. Intended usage: OBSOLETE Restrictions on usage: This media type is obsolete; current implementations should use text/javascript as the only JavaScript/ ECMAScript media type. The .mjs file extension signals that the file represents a JavaScript module. Execution environments that rely on file extensions to determine how to process inputs parse .mjs files using the Module grammar of [ECMA-262]. Author: See Author's Address section. Change controller: IESG . 4.2.3. application/x-ecmascript Type name: application Subtype name: x-ecmascript Required parameters: none Optional parameters: charset, see section 4.1 of [RFC4329]. Encoding considerations: Encoding is host dependent with differences in byte order marks, the charset parameter, and text preprocessing. Security considerations: See section 5 of [RFC4329]. Interoperability considerations: See notes in various sections of [RFC4329]. Published specification: [[RFCXXXX]] Applications which use this media type: Script interpreters as discussed in [RFC4329]. Additional information: Magic number(s): n/a File extension(s): .es, .mjs Macintosh File Type Code(s): TEXT Borins, et al. Expires May 3, 2020 [Page 7] Internet-Draft ECMAScript Media Types Updates October 2019 Person & email address to contact for further information: See Author's Address section. Intended usage: OBSOLETE Restrictions on usage: This media type is obsolete; current implementations should use text/javascript as the only JavaScript/ ECMAScript media type. The .mjs file extension signals that the file represents a JavaScript module. Execution environments that rely on file extensions to determine how to process inputs parse .mjs files using the Module grammar of [ECMA-262]. Author: See Author's Address section. Change controller: IESG 4.2.4. application/x-javascript Type name: application Subtype name: x-javascript Required parameters: none Optional parameters: charset, see section 4.1 of [RFC4329]. Encoding considerations: Encoding is host dependent with differences in byte order marks, the charset parameter, and text preprocessing. Security considerations: See section 5 of [RFC4329]. Interoperability considerations: See notes in various sections of [RFC4329]. Published specification: [[RFCXXXX]] Applications which use this media type: Script interpreters as discussed in [RFC4329]. Additional information: Magic number(s): n/a File extension(s): .js, .mjs Macintosh File Type Code(s): TEXT Borins, et al. Expires May 3, 2020 [Page 8] Internet-Draft ECMAScript Media Types Updates October 2019 Person & email address to contact for further information: See Author's Address section. Intended usage: OBSOLETE Restrictions on usage: This media type is obsolete; current implementations should use text/javascript as the only JavaScript/ ECMAScript media type. The .mjs file extension signals that the file represents a JavaScript module. Execution environments that rely on file extensions to determine how to process inputs parse .mjs files using the Module grammar of [ECMA-262]. Author: See Author's Address section. Change controller: IESG 4.2.5. text/ecmascript Type name: text Subtype name: ecmascript Required parameters: none Optional parameters: charset, see section 4.1 of [RFC4329]. Encoding considerations: Encoding is host dependent with differences in byte order marks, the charset parameter, and text preprocessing. Security considerations: See section 5 of [RFC4329]. Interoperability considerations: See notes in various sections of [RFC4329]. Published specification: [[RFCXXXX]] Applications which use this media type: Script interpreters as discussed in [RFC4329]. Additional information: Magic number(s): n/a File extension(s): .es, .mjs Macintosh File Type Code(s): TEXT Borins, et al. Expires May 3, 2020 [Page 9] Internet-Draft ECMAScript Media Types Updates October 2019 Person & email address to contact for further information: See Author's Address section. Intended usage: OBSOLETE Restrictions on usage: This media type is obsolete; current implementations should use text/javascript as the only JavaScript/ ECMAScript media type. The .mjs file extension signals that the file represents a JavaScript module. Execution environments that rely on file extensions to determine how to process inputs parse .mjs files using the Module grammar of [ECMA-262]. Author: See Author's Address section. Change controller: IESG 4.2.6. text/javascript1.0 Type name: text Subtype name: javascript1.0 Required parameters: none Optional parameters: charset, see section 4.1 of [RFC4329]. Encoding considerations: Encoding is host dependent with differences in byte order marks, the charset parameter, and text preprocessing. Security considerations: See section 5 of [RFC4329]. Interoperability considerations: See notes in various sections of [RFC4329]. Published specification: [[RFCXXXX]] Applications which use this media type: Script interpreters as discussed in [RFC4329]. Additional information: Magic number(s): n/a File extension(s): .js, .mjs Macintosh File Type Code(s): TEXT Borins, et al. Expires May 3, 2020 [Page 10] Internet-Draft ECMAScript Media Types Updates October 2019 Person & email address to contact for further information: See Author's Address section. Intended usage: OBSOLETE Restrictions on usage: This media type is obsolete; current implementations should use text/javascript as the only JavaScript/ ECMAScript media type. The .mjs file extension signals that the file represents a JavaScript module. Execution environments that rely on file extensions to determine how to process inputs parse .mjs files using the Module grammar of [ECMA-262]. Author: See Author's Address section. Change controller: IESG 4.2.7. text/javascript1.1 Type name: text Subtype name: javascript1.1 Required parameters: none Optional parameters: charset, see section 4.1 of [RFC4329]. Encoding considerations: Encoding is host dependent with differences in byte order marks, the charset parameter, and text preprocessing. Security considerations: See section 5 of [RFC4329]. Interoperability considerations: See notes in various sections of [RFC4329]. Published specification: [[RFCXXXX]] Applications which use this media type: Script interpreters as discussed in [RFC4329]. Additional information: Magic number(s): n/a File extension(s): .js, .mjs Macintosh File Type Code(s): TEXT Borins, et al. Expires May 3, 2020 [Page 11] Internet-Draft ECMAScript Media Types Updates October 2019 Person & email address to contact for further information: See Author's Address section. Intended usage: OBSOLETE Restrictions on usage: This media type is obsolete; current implementations should use text/javascript as the only JavaScript/ ECMAScript media type. The .mjs file extension signals that the file represents a JavaScript module. Execution environments that rely on file extensions to determine how to process inputs parse .mjs files using the Module grammar of [ECMA-262]. Author: See Author's Address section. Change controller: IESG 4.2.8. text/javascript1.2 Type name: text Subtype name: javascript1.2 Required parameters: none Optional parameters: charset, see section 4.1 of [RFC4329]. Encoding considerations: Encoding is host dependent with differences in byte order marks, the charset parameter, and text preprocessing. Security considerations: See section 5 of [RFC4329]. Interoperability considerations: See notes in various sections of [RFC4329]. Published specification: [[RFCXXXX]] Applications which use this media type: Script interpreters as discussed in [RFC4329]. Additional information: Magic number(s): n/a File extension(s): .js, .mjs Macintosh File Type Code(s): TEXT Borins, et al. Expires May 3, 2020 [Page 12] Internet-Draft ECMAScript Media Types Updates October 2019 Person & email address to contact for further information: See Author's Address section. Intended usage: OBSOLETE Restrictions on usage: This media type is obsolete; current implementations should use text/javascript as the only JavaScript/ ECMAScript media type. The .mjs file extension signals that the file represents a JavaScript module. Execution environments that rely on file extensions to determine how to process inputs parse .mjs files using the Module grammar of [ECMA-262]. Author: See Author's Address section. Change controller: IESG 4.2.9. text/javascript1.3 Type name: text Subtype name: javascript1.3 Required parameters: none Optional parameters: charset, see section 4.1 of [RFC4329]. Encoding considerations: Encoding is host dependent with differences in byte order marks, the charset parameter, and text preprocessing. Security considerations: See section 5 of [RFC4329]. Interoperability considerations: See notes in various sections of [RFC4329]. Published specification: [[RFCXXXX]] Applications which use this media type: Script interpreters as discussed in [RFC4329]. Additional information: Magic number(s): n/a File extension(s): .js, .mjs Macintosh File Type Code(s): TEXT Borins, et al. Expires May 3, 2020 [Page 13] Internet-Draft ECMAScript Media Types Updates October 2019 Person & email address to contact for further information: See Author's Address section. Intended usage: OBSOLETE Restrictions on usage: This media type is obsolete; current implementations should use text/javascript as the only JavaScript/ ECMAScript media type. The .mjs file extension signals that the file represents a JavaScript module. Execution environments that rely on file extensions to determine how to process inputs parse .mjs files using the Module grammar of [ECMA-262]. Author: See Author's Address section. Change controller: IESG 4.2.10. text/javascript1.4 Type name: text Subtype name: javascript1.4 Required parameters: none Optional parameters: charset, see section 4.1 of [RFC4329]. Encoding considerations: Encoding is host dependent with differences in byte order marks, the charset parameter, and text preprocessing. Security considerations: See section 5 of [RFC4329]. Interoperability considerations: See notes in various sections of [RFC4329]. Published specification: [[RFCXXXX]] Applications which use this media type: Script interpreters as discussed in [RFC4329]. Additional information: Magic number(s): n/a File extension(s): .js, .mjs Macintosh File Type Code(s): TEXT Borins, et al. Expires May 3, 2020 [Page 14] Internet-Draft ECMAScript Media Types Updates October 2019 Person & email address to contact for further information: See Author's Address section. Intended usage: OBSOLETE Restrictions on usage: This media type is obsolete; current implementations should use text/javascript as the only JavaScript/ ECMAScript media type. The .mjs file extension signals that the file represents a JavaScript module. Execution environments that rely on file extensions to determine how to process inputs parse .mjs files using the Module grammar of [ECMA-262]. Author: See Author's Address section. Change controller: IESG 4.2.11. text/javascript1.5 Type name: text Subtype name: javascript1.5 Required parameters: none Optional parameters: charset, see section 4.1 of [RFC4329]. Encoding considerations: Encoding is host dependent with differences in byte order marks, the charset parameter, and text preprocessing. Security considerations: See section 5 of [RFC4329]. Interoperability considerations: See notes in various sections of [RFC4329]. Published specification: [[RFCXXXX]] Applications which use this media type: Script interpreters as discussed in [RFC4329]. Additional information: Magic number(s): n/a File extension(s): .js, .mjs Macintosh File Type Code(s): TEXT Borins, et al. Expires May 3, 2020 [Page 15] Internet-Draft ECMAScript Media Types Updates October 2019 Person & email address to contact for further information: See Author's Address section. Intended usage: OBSOLETE Restrictions on usage: This media type is obsolete; current implementations should use text/javascript as the only JavaScript/ ECMAScript media type. The .mjs file extension signals that the file represents a JavaScript module. Execution environments that rely on file extensions to determine how to process inputs parse .mjs files using the Module grammar of [ECMA-262]. Author: See Author's Address section. Change controller: IESG 4.2.12. text/jscript Type name: text Subtype name: jscript Required parameters: none Optional parameters: charset, see section 4.1 of [RFC4329]. Encoding considerations: Encoding is host dependent with differences in byte order marks, the charset parameter, and text preprocessing. Security considerations: See section 5 of [RFC4329]. Interoperability considerations: See notes in various sections of [RFC4329]. Published specification: [[RFCXXXX]] Applications which use this media type: Script interpreters as discussed in [RFC4329]. Additional information: Magic number(s): n/a File extension(s): .js, .mjs Macintosh File Type Code(s): TEXT Borins, et al. Expires May 3, 2020 [Page 16] Internet-Draft ECMAScript Media Types Updates October 2019 Person & email address to contact for further information: See Author's Address section. Intended usage: OBSOLETE Restrictions on usage: The .mjs file extension signals that the file represents a JavaScript module. Execution environments that rely on file extensions to determine how to process inputs parse .mjs files using the Module grammar of [ECMA-262]. Author: See Author's Address section. Change controller: IESG 4.2.13. text/livescript Type name: text Subtype name: livescript Required parameters: none Optional parameters: charset, see section 4.1 of [RFC4329]. Encoding considerations: Encoding is host dependent with differences in byte order marks, the charset parameter, and text preprocessing. Security considerations: See section 5 of [RFC4329]. Interoperability considerations: See notes in various sections of [RFC4329]. Published specification: [[RFCXXXX]] Applications which use this media type: Script interpreters as discussed in [RFC4329]. Additional information: Magic number(s): n/a File extension(s): .js, .mjs Macintosh File Type Code(s): TEXT Person & email address to contact for further information: See Author's Address section. Borins, et al. Expires May 3, 2020 [Page 17] Internet-Draft ECMAScript Media Types Updates October 2019 Intended usage: OBSOLETE Restrictions on usage: The .mjs file extension signals that the file represents a JavaScript module. Execution environments that rely on file extensions to determine how to process inputs parse .mjs files using the Module grammar of [ECMA-262]. Author: See Author's Address section. Change controller: IESG 4.2.14. text/x-ecmascript Type name: text Subtype name: x-ecmascript Required parameters: none Optional parameters: charset, see section 4.1 of [RFC4329]. Encoding considerations: Encoding is host dependent with differences in byte order marks, the charset parameter, and text preprocessing. Security considerations: See section 5 of [RFC4329]. Interoperability considerations: See notes in various sections of [RFC4329]. Published specification: [[RFCXXXX]] Applications which use this media type: Script interpreters as discussed in [RFC4329]. Additional information: Magic number(s): n/a File extension(s): .es, .mjs Macintosh File Type Code(s): TEXT Person & email address to contact for further information: See Author's Address section. Intended usage: OBSOLETE Borins, et al. Expires May 3, 2020 [Page 18] Internet-Draft ECMAScript Media Types Updates October 2019 Restrictions on usage: The .mjs file extension signals that the file represents a JavaScript module. Execution environments that rely on file extensions to determine how to process inputs parse .mjs files using the Module grammar of [ECMA-262]. Author: See Author's Address section. Change controller: IESG 4.2.15. text/x-javascript Type name: text Subtype name: x-javascript Required parameters: none Optional parameters: charset, see section 4.1 of [RFC4329]. Encoding considerations: Encoding is host dependent with differences in byte order marks, the charset parameter, and text preprocessing. Security considerations: See section 5 of [RFC4329]. Interoperability considerations: See notes in various sections of [RFC4329]. Published specification: [[RFCXXXX]] Applications which use this media type: Script interpreters as discussed in [RFC4329]. Additional information: Magic number(s): n/a File extension(s): .js, .mjs Macintosh File Type Code(s): TEXT Person & email address to contact for further information: See Author's Address section. Intended usage: OBSOLETE Restrictions on usage: The .mjs file extension signals that the file represents a JavaScript module. Execution environments that rely Borins, et al. Expires May 3, 2020 [Page 19] Internet-Draft ECMAScript Media Types Updates October 2019 on file extensions to determine how to process inputs parse .mjs files using the Module grammar of [ECMA-262]. Author: See Author's Address section. Change controller: IESG 5. References 5.1. Normative References [ECMA-262] Ecma International, "Standard ECMA-262: ECMAScript Language Specification", August 2017, . [RFC4329] Hoehrmann, B., "Scripting Media Types", RFC 4329, DOI 10.17487/RFC4329, April 2006, . 5.2. Informative References [HTML] WHATWG, "HTML Living Standard", August 2017, . [SPECTRE] Kocher, P., Fogh, A., Gerkin, D., Gruss, D., Haas, W., Hamburg, M., Lipp, M., Mangard, S., Prescher, T., Schwarz, M., and Y. Yarom, "Spectre Attacks: Exploiting Speculative Execution", January 2018, . [TC39-MIME-ISSUE] TC39, "Add `application/javascript+module` mime to remove ambiguity", August 2017, . Appendix A. Acknowledgements The authors would like to thank Suresh Krishnan, Alexey Melnikov, Mark Nottingham, James Snell, Adam Roach, and Allen Wirfs-Brock for their guidance throughout this process. Authors' Addresses Borins, et al. Expires May 3, 2020 [Page 20] Internet-Draft ECMAScript Media Types Updates October 2019 Myles Borins Google Email: mylesborins@google.com Mathias Bynens Google Email: mths@google.com Matthew A. Miller Mozilla Email: linuxwolf+ietf@outer-planes.net Bradley Farias Email: bradley.meck@gmail.com Borins, et al. Expires May 3, 2020 [Page 21]