This video shows ICANN stakeholders lending their support to Universal Acceptance. This is the technical term that makes it possible for the internet to be truly international and multilingual, both in website's content and also in domain names and web addresses.
As the internet has expanded to a thousand new domain extensions (known in the industry as new generic top level domains, or new gTLDs), not all websites have yet been updated or upgraded to support these new domain extensions for user email addresses, sometimes used for username login access and for vital on-going communications.
You can get a sense of how popular websites are handling user emails that have new gTLDs from this universal acceptance testing conducted by the .CLUB top-level registry. (in summary, 65% passed, and that means 35% are not yet fully-supporting new gTLD emails.)
[UA-Discuss] Acceptance Tests done for sites
Dirk Bhagat dirk at get.club
Wed May 18 13:15:55 UTC 2016
As part of .Club's effort prior to UASG, .club had hand tested around 600 popular sites [mostly from Alexa] for their ability to accept *.club* email addresses.
Here is the testing spreadsheet we used: https://docs.google.com/spreadsheets/d/1WIhKvD7mvK7xHyRWGNK1AcDTK7Yhdt69RXuPKcpTIZA/edit?usp=sharing
This spreadsheet breaks the list down into a few categories:
Although there is a lot more work to be done, I believe it's a good starting point.
-- Dirk Bhagat
.CLUB DOMAINS LLC.
100 SE 3rd Ave, Suite 1310
Fort Lauderdale, Fl, 33394
Now there's a report that provides hard data, quantitative data, for how Universal Acceptance is not yet universal and it's got a ways to go. Quote, "The problems identified in the report resulted in a larger than expected number of IDN TLDs being unresolvable, clearly an issue for Universal Acceptance."
From the ICANN and UASG Announce Results of Universal Acceptance Study for New gTLDs --
ICANN, in conjunction with the Universal Acceptance Steering Group (UASG) announced the availability of a new report: An Analysis of New gTLD Universal Acceptance. Universal Acceptance (UA) is the concept of removing all technical barriers that might hinder a user from accessing any name in any top-level domain (TLD) from any web browser, email client, or other Internet application on any computer or electronic device. The report, sponsored by ICANN, is available here [PDF, 1.63 MB].