IDN/EAI failure

User Help for Mozilla Thunderbird
Post Reply
voffka
Posts: 5
Joined: June 24th, 2022, 12:00 am

IDN/EAI failure

Post by voffka »

Unable to add an IDN/EAI address as an alternate account address :-(

"тест@тест.укр" => "B5AB@B5AB.C:@"
"тест@xn--e1aybc.xn--j1amh" => "B5AB@xn--e1aybc.xn--j1amh"
User avatar
tanstaafl
Moderator
Posts: 49647
Joined: July 30th, 2003, 5:06 pm

Re: IDN/EAI failure

Post by tanstaafl »

IDN stands for "internationalized domain name". Thunderbird added support for accented and non-latin characters etc. in domain names a long time ago but its not clear if they eventually added support for that to the username portion of the email address yet (support for RFC 6532).

http://kb.mozillazine.org/International_characters needs updating but mentions: "International characters are supported in domain names (IDN) but they are not supported in the username portion of a email address. Non-ASCII characters in the username isn't part of the IDN spec, its part of supporting UTF8 in headers in RFC 6532 (Internationalized Email Headers). Thunderbird doesn't support RFC 6532 yet"

https://www.thunderbird.net/en-US/thund ... easenotes/ says "Mail address display at header pane displayed incorrectly if the address contains UTF-8 according to RFC 6532" is fixed.

https://github.com/whatwg/html/issues/4562 mentions: "RFC 6532 was not supported for a long time in many software apps (f.x. Thunderbird makes really strange things when receives non-encoded UTF-8 mail compilant with RFC 6532 - it's still open in Bugzilla) but up-to-date mail servers allow to create such accounts and send such mails (Postfix has support for it since ~2015)"

Supposedly the new account wizard still has a problem with IDN . IDN support is controlled by network.enableIDN , which I think defaults to true.

https://bugzilla.mozilla.org/show_bug.cgi?id=811272
https://www.tenforums.com/tutorials/104 ... ndows.html
https://en.wikipedia.org/wiki/International_email
voffka
Posts: 5
Joined: June 24th, 2022, 12:00 am

Re: IDN/EAI failure

Post by voffka »

From Thunderbird, you can send mail to "тест@тест.укр" (the address is given as an example, a different one was used for the test). But I can't make "тест@тест.укр" the sender's address ((
User avatar
tanstaafl
Moderator
Posts: 49647
Joined: July 30th, 2003, 5:06 pm

Re: IDN/EAI failure

Post by tanstaafl »

I'd assume that's because Thunderbird doesn't care if the recipients email address is a international address or not. Its mainly up to the recipients email provider and their email client to implement the relevant standards.

Thunderbird would need to support the relevant standards to make a international address an accounts email address or use it in a multiple identity. However, the bottom of the From: drop down list has "Customize From Address". Its possible it may let you use a international email address there.

I'm not the best person to try to help you, I have no need to deal with non-Latin characters sets.

https://bugzilla.mozilla.org/show_bug.cgi?id=235312 (Support for UTF-8 mail server hostnames and email addresses in account settings) is still NEW. It was opened 19 years ago.
voffka
Posts: 5
Joined: June 24th, 2022, 12:00 am

Re: IDN/EAI failure

Post by voffka »

I configure the sender address in the account settings so that it is added to the drop-down list of alternative addresses available when writing a message. Alternate EAI/IDN email gets garbled when added ((
User avatar
tanstaafl
Moderator
Posts: 49647
Joined: July 30th, 2003, 5:06 pm

Re: IDN/EAI failure

Post by tanstaafl »

Then you're out of luck.

As an experiment I created a multiple identity using plus addressing where I used accented characters in the optional string. When I sent the message using 102.BL8 it didn't report an error but no copy was saved and it was never sent. Weird. I'm going to file a bug report. With a little luck I might be able to get a statement on whether RFC 6532 is supported, and does it only apply to UTF-8 character set encoding.
voffka
Posts: 5
Joined: June 24th, 2022, 12:00 am

Re: IDN/EAI failure

Post by voffka »

Thunderbird transmits addresses as is, i.e. the domain name is not resolved by PunyCode. This does not sit well with MTAs, which have not been specially modified to ignore and correct this MUA error.
voffka
Posts: 5
Joined: June 24th, 2022, 12:00 am

Re: IDN/EAI failure

Post by voffka »

It also, Thunderbird doesn't reverse-encode from PunyCode to UTF-8 when rendering fields "From", "To", etc. in the received message. Which is not convenient to use. In short, declaring implementation and implementing are two big differences ;-)
Post Reply