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ThunderBird doesn’t handle incomplete email address in recipient/To Field

  • 13 replies
  • 2 have this problem
  • 2 views
  • Last reply by Madasan

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Issue Description: ThunderBird allows mail with invalid/incomplete email domain in recipient/To email address. EmailID with incomplete mail domain are allowed and not handled by Thunderbird. Example: missing “.com” in the email address. ThunderBird client sends out the email to MailServer. The incomplete email address should be handled by Thunderbird and should alert user of invalid email entry. Please look into fixing the issue and let me know once the fix release is available to me.

Steps to recreate issue: 1. From ThunderBird Email Client, open/Write a new email window 2. In the To address field, key in “invalidemail@invaliddomain”, key subject and email body content 3. Click Send button (Refer to attached screen "ThunderBird_incomplete_recipient.png" for incomplete To/emailID)

Expected from Thunderbird: Thunderbird should handle the incomplete email address and alert user of the invalid email/To address, alert of something similar to as shown in attached screen "Expected_alert.png" example.

Issue Description: ThunderBird allows mail with invalid/incomplete email domain in recipient/To email address. EmailID with incomplete mail domain are allowed and not handled by Thunderbird. Example: missing “.com” in the email address. ThunderBird client sends out the email to MailServer. The incomplete email address should be handled by Thunderbird and should alert user of invalid email entry. Please look into fixing the issue and let me know once the fix release is available to me. Steps to recreate issue: 1. From ThunderBird Email Client, open/Write a new email window 2. In the To address field, key in “invalidemail@invaliddomain”, key subject and email body content 3. Click Send button (Refer to attached screen "ThunderBird_incomplete_recipient.png" for incomplete To/emailID) Expected from Thunderbird: Thunderbird should handle the incomplete email address and alert user of the invalid email/To address, alert of something similar to as shown in attached screen "Expected_alert.png" example.
Attached screenshots

All Replies (13)

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I'm puzzled by why your incomplete address isn't shown in red. This is the usual way for Thunderbird to alert a user to a non-validated address.

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Hi Zenos! Thx for checking on the issue.

The incomplete address did appear in red colour the first time I sent (attached sample screen with incomplete email). In subsequent new mails I have used same incomplete email, now they appear normal/black. I guess, known contacts & already used emailID would be shown as normal colour font in ThunderBird.

There is no alert popup received for incomplete emailID entered, ThunderBird doesn't alert and doesn't stop.

I guess my second image attachment mislead you (image with pop alert). That image is my expectation from Thunderbird - it should prompt when it encounters an incomplete emailid. In this case of incomplete email, ThunderBird would not alert user as it failed to detect the incomplete email domain info. This bug need to be fixed by Mozilla team.

Do have an idea on how long does Mozilla team takes to come back with a fix release?

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Ok, sending the mail will add it to the address book. Once in the address book it is no longer an unknown address.

But of greater importance is that the address is not invalid as far as the form of an email address goes. There is nothing invalif about Matt@localserver as an email address. as long as the DNS can locate localserver and it has a mail server. I have used very similar naming conventions in local mail systems in the past.

Even the convention of .com .net is not set in stone. there are now hundreds of valid TLD's. An internet email address might well be Me@Melbourne as Melbourne is now a valid TLD

To quote RFC 5321

2.3.5. Domain Names

A domain name (or often just a "domain") consists of one or more components, separated by dots if more than one appears. In the case of a top-level domain used by itself in an email address, a single string is used without any dots. This makes the requirement, described in more detail below, that only fully-qualified domain names appear in SMTP transactions on the public Internet, particularly important where top-level domains are involved. These components ("labels" in DNS terminology, RFC 1035 [2]) are restricted for SMTP purposes to consist of a sequence of letters, digits, and hyphens drawn from the ASCII character set [6]. Domain names are used as names of hosts and of other entities in the domain name hierarchy. For example, a domain may refer to an alias (label of a CNAME RR) or the label of Mail eXchanger records to be used to deliver mail instead of representing a host name. See RFC 1035 [2] and Section 5 of this specification.

The domain name, as described in this document and in RFC 1035 [2], is the entire, fully-qualified name (often referred to as an "FQDN"). A domain name that is not in FQDN form is no more than a local alias. Local aliases MUST NOT appear in any SMTP transaction.

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Hi Matt,

Thx for the response and useful RFC info.

Your example Me@Melbourne is not a valid email address in Outlook client and even other email engines like Gmail doesn't accept/allow it and couldn't mail out. I guess that this type of TLD is still not allowed in SMTP world. Further, the RFC wants us to stick to "only fully-qualified domain names appear in SMTP transactions on the public Internet". So ThunderBird should refrain from allowing @hostname alone type of address format.

Even if I accept email client can allow me@localhost as valid address, I still feel ThunderBird is not doing enough to resolve/validate at least the @justDomain to be a local address or not. (something like client would be able to resolve localhost/localserver as local system SMTP server). ThunderBird should reject emails that doesn't resolve to localserver.

I still feel Mozilla- ThunderBird team should address this issue and come up with a fix to prevent @localhost type email recipient. It is better to follow the same standard recipient format/features what other email clients do.

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Did you not understand, that RFC states as you quotes. Fully qualified domain. as .melbourne is a completely valid TLD then an email address Matt@melbourne is by default a fully qualified domain name. I quote again " In the case of a top-level domain used by itself in an email address, a single string is used without any dots." "It does not matter if there is no derver on the internet, that makes an email address with no dots in the domain part valid.

Now in the past the internet has been full of websites and email programs that used regular expressions to determine what is a valid email address. Unfortunately most of those folk have never actually read the description. The assumed. Even large providers like Yahoo will not allow you to create and address with the full range of Localpasrts.

The only way that Thunderbird could reliably verify an email address is to connect the mail server for the domain in the email address, open a connection and ask it if it can deliver mail.

But there are some real logistical issues with that, not the least of which is most ISPs these days do not allow communications on Port 25, the port used to connect to mail exchangers.

The second part of this is that once you have written that much code, you might as well implement the whole SMTP RFC. as there is not much left after you have connected, negotiated a transmission and attempted to deliver mail. The only way is to attempt delivery and get a acceptance or an error.

Bit of an issue given my first point.

That same RFC says that the local part is case sensitive, but that is not something you see implemented these days, Windows users in some cases unaware that their keyboard has a shift key. Windows has no penalties for poor use of case. But server vthsat implement it do still exist.

As far as outlook validating addresses.they are probably using regular expressions as well. Try it with some of these valid email addresses.

   "Abc\@def"@example.com
   "Fred Bloggs"@example.com
   "Joe\\Blow"@example.com
   "Abc@def"@example.com
   customer/department=shipping@example.com
   \$A12345@example.com
   !def!xyz%abc@example.com
   _somename@example.com

Basically computers can not replace humans when it comes to looking and seeing.

Then we have folk that want even the requirement for an @domain part removed.https://bugzilla.mozilla.org/show_bug.cgi?id=312818 They have been waiting since 2005 for their bug.

But you are welcome to file our own enhancement request. But I really don't see how developers can reconcile your want with that expressed in Bug 312818 But be sure that you address the RFC in your bug. The developers have no interest in the poor practices employed elsewhere. Thunderbird is RFC complaint. So if you want your validation, you will have to request it within the scope of the RFC. If Microsoft have the dog by the tail is no reason for everyone to go haring off after them. So because they do it is NOT sufficient to get you more than 1 second, while they close the bug as invalid.

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In first image where you have written 'cdfasfadsfsa' You said that the first time you entered that 'incomplete' email address, the lettering was red. This was thunderbird telling you that the email address was not in your address book and is drawing your attention to that email address.

when trying to send - obviously you ignored the red lettering trying to draw your attention to the email address - then when tried to send you got an error message drawing your attention to that email address which is obviously incorrect. So you did get a prompt.

Thunderbird does not check the spelling - that is down to you, but the pop up prompt to say you have something wrong is helpful.

As it is now black then the entry has been placed in one of your address books - probably 'Collected Addresses' - editing that stored address will resolve the issue of you selecting that spelling of the email address.

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Hi Toad-Hall,

Thanks for the response, but issue is different. For your quick understanding of the issue... Thunderbird accepts incomplete email address something like "you@justdomainnamewithoutdotcom"

Request you to read rest of the replies including Matt's, to understand the issue better.

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Hi Matt,

Thanks again for response, I see lot of information and other regular expressions. On a different day I would very happy/interested in it, but sorry not in this case.

I'm not trying to be rude here, but wanted to get straight to point and would like to restate - restOfWolrd are not able to email to you@Melbourne. Neither Yahoo, Gmail, Outlook accept this email address as valid one. From what you state, I find it very strange. i.e.. When whole/Rest of the world sees this email as incomplete/unrecognisable and odd, Thunderbird alone accepts it as correct one. Would like to ask -What is the purpose of having a Thunderbird feature that is not useful to world? This feature is an nuisance rather being useful, it is causing issue. Thunderbird allows an incomplete email, anybody would agree to it.

Would also like to ask, have you tried sending email to you@Melbourne? The reason I ask because, it is possible that you might have overlooked and stating that kind of email address existence without validating it. You would not be able to send email to such emailID practically (I did validate them).

I'm writing to see if Thunderbird can fix it to resolve an issue, I'm not asking for enhancing the client. I would like this to be treated as a bug. Let me know if Thunderbird cannot fix it. If you are the one deciding on fix’s fate, I would request you to discuss with your team to see if the issue is valid one before you reject the issue/bug.

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You have been told where to report a bug:
Then we have folk that want even the requirement for an @domain part removed. https://bugzilla.mozilla.org/show_bug.cgi?id=312818 They have been waiting since 2005 for their bug.
No-one here on this forum has the authority to either progress or veto work on a bug.
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Hi Zenos,

Thx! I have submitted the issue https://bugzilla.mozilla.org/show_bug.cgi?id=1244494

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Suvega said

restOfWolrd are not able to email to you@Melbourne. Neither Yahoo, Gmail, Outlook accept this email address as valid one.

Not relevant. If the RFC says is is valid it is valid. It is not a debate.

I don't care about anything else. Neither should anyone involved in email client development. All that is needed is for me to have a server on my network which resolves to Melbourne in the hear and now. How all those web sites choose to implement the RFC is their business, but as they are not behind a firewall and will most definitely require to operate on the wider internet and there are no internet servers using the TLD only as far as I am aware they can get away without client complaint.

Not so Thunderbird. It is a client within the local network. Outlook parses addresses as Internet addresses or local addresses. This is because primarily Outlook is an Exchange client, not an email client. But I digress..

If you want the RFC changed I suggest you approach the internet engineering task force with a new draft RFC. But a bug requesting Thunderbird take a stance that is not RFC complaint is very unlikely to fly without a strong argument. That you think it should is really not any sort of argument at all. That Thunderbird is alone in it's compliance is a selling point. Not a reason to change.

From what you state, I find it very strange. i.e.. When whole/Rest of the world sees this email as incomplete/unrecognisable and odd, Thunderbird alone accepts it as correct one. Would like to ask -What is the purpose of having a Thunderbird feature that is not useful to world?

It is very useful to those operating internal serves and as the bug I linked to points out those people want the current requirement to have something after the @ removed. They would scream bloody murder at your suggestion. So prepare your arguments well. You are already aware there is a use case for removing all validity checking, incliding there being an @

This feature is an nuisance rather being useful, it is causing issue. Thunderbird allows an incomplete email, anybody would agree to it.

Actually I don't agree. It looks to me like the only one participating in this thread that agrees is YOU.

Would also like to ask, have you tried sending email to you@Melbourne? The reason I ask because, it is possible that you might have overlooked and stating that kind of email address existence without validating it.

I have no doubt the domain does not exist as far as delivery of email is connecerned. That does not make it wrong or invalid. Only undeliverable a very different thing.

I'm writing to see if Thunderbird can fix it to resolve an issue, I'm not asking for enhancing the client. I would like this to be treated as a bug.
As I said before your welcome to file a bug.
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I didn't know it is going to get personal, why have you used “YOU”? Requesting you to remain professional, please cut out personalities and stay away from “bloody/scream/murder/YOU/don't care ” in your comments. We do care about what is being replied about our concerns and how it is being treated. Hope Thunderbird forum takes note of what you are posting and I request Thunderbird forum also to moderate your comments/responses/personalities.

The issue raised by me is based on complaints and issues faced by my users. It means that more people (than me) are suffering with Thunderbird’s inability to handle incomplete email address. So please understand it is not just me reporting this issue and more people are in agreement with my raised issue. I never asked you to assume it was only me facing this issue.

Unfortunately, only a handful have responded to my question here in the forum (possibly, low forum user base). If you read again all the question’s comments, others who have responded to this question also don’t agree with you either. In fact, one of them has asked me to go ahead and file it as a bug which I have also did raise. So, you can take back your none agrees to my question liner.

From your responses you have pointed out that meOryou@Melbourne is useful to mere internal servers and this not valid elsewhere. Then in this case, it is time for Thunderbird to handle entered email address is an valid internal one and otherwise flag/reject it as incomplete/unrecognisable address (for external). Since I'm working with many users who are facing this issue, it would be nicer for open source Thunderbird to enhance/feature it for users mailing out to external domains.

I feel there is no necessary to apply/request for RFC amendments in this case (external recipient email address). If Thunderbird allows incomplete recipient address for some reason, I just had to know that reason in a simple direct answer. Your responses were never simpler/straight to the point, had too much of other information. I had lot of difficulty in inferring the answer from your responses. From what you mentioned so far, I have arrived at better & simpler answer (like) - the feature is not a bug and it is used for internal servers purpose and it remains as a feature.

I don’t have strong reason to agree with Thunderbird’s RFC abiding for this type when it is actually causing issue to many users (in my case). Thunderbird team should properly validate usefulness of a probable fix and agree/disagree on rejecting on the bug. Since Thunderbird is for open source community, I feel it can expand to user requirements and enhancements. If my case is treated as an enhancement, let me know what is the way to raise enhancement requests.

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I will be closing closing this thread as this is getting off-topic. This is a support forum so the discussion should strictly be related to support requests. For product feedback discussions, product improvement suggestions, feature requests etc please file the appropriate bugs. I understand such topics can be frustrating but we should try to keep the debate civil. It's ok to disagree, it's not ok to be mean :)

PS: feel free to PM me for any issue you might have with this.

I will be closing this thread as this is getting off-topic. This is a support forum so the discussion should strictly be related to support requests. For product feedback discussions, product improvement suggestions, feature requests etc please file the appropriate bugs. I understand such topics can be frustrating but we should try to keep the debate civil. It's ok to disagree, it's not ok to be mean :)

PS: feel free to PM me for any issue you might have with this.

Later edit It looks like for Thunderbird topics in particular, product feedback discussions are ok so I'll keep the topic open. However I would encourage everybody to file bugs when necessary as they might be more efficient than a debate :). And please keep the conversation civil.

Modified by Madasan