How do "download" and "template" relate to each other?

Zenos said

How do "download" and "template" relate to each other?

An email template refers to when creating an email for email marketing with html and css. Which will have a various amount of characters based on how code there is. I checked a few MailChimp templates and they have typically 50K to 60K characters or more.

Download refers when a user opens Thunderbird it downloads messages from the server to their computer.

The question is, does Thunderbird have any limit on the maximum number of characters it can download for an email. I've been told there is a roughly 50K character limit (meaning templates that are more than that wouldn't download or would be trimmed.

I find that hard to believe as I've never heard that before or see any information on Mozilla mentioning that limit. But I wanted to confirmation from Mozilla on whether there is any such character limit or if maybe there was a while back so I can provided a confirmed answer back to the person who originally mentioned the 50K limit.

Thanks!

I still don't see where "download" and "template" are conjoined. Your template is just a file, and it probably needs to be on your own computer so there's no download involved for you to be able to make use of it.

When we encounter a limit on email message size, it's usually expressed in terms of maximum size of attachment, and that is generally a policy based limit, not a strictly technical limit. Since it's often set at a value of 10 MB this tells me that email itself has no problem with messages rather larger than your putative limit.

I don't know of any such limit in Thunderbird. I'd suspect that your informant had encountered a practical limit possibly due to an ISP or email provider's policy settings, or was using an unreliable connection that couldn't stay up long enough without exceeding a permitted number of resends and retries.

Send yourself or a colleague a big message and see what happens. Try a mix of email clients at both ends.

Not quite sure what you mean by, "I still don't see where "download" and "template" are conjoined." Other than once again by template I'm referring to the code/content of an email sent through newsletter software. When using Constant Contact, MailChimp, CampaignMonitor, VerticalResponse, or such they request you upload a newsletter template and then add your content. Those templates/emails contain a certain number of characters.

When those emails are sent to recipients using a mail application like Thunderbird, they are downloaded to that uses computer to be viewed.

While of course attachments relate to how much your email service provider allow, this is just in relation to a potential limit on the number of characters and email/template can contain to be downloaded to a user using thunderbird.

I personally, have never heard of any mention of thunderbird (or any modern email client) being limited on downloading a template based on the number of characters in it, and certainly not as a limit as low as roughly 50K characters. As MailChimp sends 600 million emails a day for instance to users with their templates that include more than 50K characters and I imagine they would know if the 1% of users using thunderbird faced such an issue. And they are not aware of this limit either they say. But they suggested I check with Mozilla for confirmation.

So while once again I don't think such a limit exists, I wanted to see if Mozilla could confirm one way or the other, so I can pass that information directly on. I can try reaching Mozilla / Thunderbird on Twitter as well to see if I can reach a staff member there who might know.

Thanks for your help!

To cut to the chase, your chasing an urban myth.

Thunderbird sees an email as a file and downloads it. attachments, text code and images. They are all encoded in the file in mime format. The size of individual mails is really more a factor of what the server allows.

As stupid as it may appear there are video editing houses who send mails in the hundred of megabytes in a regular bases and complain most vociferously if delivery is delayed. Anyone sending cad files will also be familiar with huge mails as well. 15 years ago my ISP had a limit of 5Mb per mail. Hotmail used to limit a mail to 25Mb in recent years all those appear to have disappeared as well. 50k has never been a limit in mail that I have ever heard of. Not since the late 1980s anyway.

Thanks for the response Matt. Just to note the client who mentioned this, didn't mention the limit in regards to attachment sizes, which would of course be dependent on the mail provider such as 25MB for gmail 10MB or 5MB for others.

But rather that an email template can't have more than roughly 50 thousand characters, otherwise the whole email won't be downloaded/rendered in Thunderbird. And by characters that is if I one where to copy and paste the entire email template into a character counter software, most responsive MailChimp templates are roughly 50K to 60K "characters" and would assume if there was such a limit on the max number of characters that it would be somewhere on mozilla support or online.

So I'm 99.9% sure this isn't correct, but was hoping to get a finite answer that there is, and hasn't ever been (in modern times), a limit on the maximum number characters an email template can have to be downloaded to thunderbird. That is of course unless the number of text characters was so enourmous that it made the template itself more than 5MB, 10MB etc, but that would enormously larger than only 50K characters.

So far it sounds like there is no such limit thankfully.

I can't see it matters where the content came from. Your theory is that a "large" message (however it is constructed) will somehow fail in Thunderbird. Whether or not you used a template seems to me to be irrelevant.

We don't know of any such limit. Thunderbird does have some odd limits, such as "approximately 60 addresses" (link) but that appears to be an accidental limit imposed by the size of a buffer and not an intentional design specification. I would surmise that if Thunderbird does choke on any "large" message it will be some accidental buffer size limit at root.

I have just sent, and received, a large message (237 KB on receipt) via two different IMAP accounts. A glance at the "size" column (which I don't normally have enabled) in one of my folders indicates that received messages frequently exceed your 50 KB limit.

can Firefox render a 100kb age? Sure can, I download HTML/Text files that large often. Thunderbird uses the exact same rendering engine. Now thee might be some limit to the inline CSS, but I have never heard anything.

For completeness, I have also saved my big message as a template and have retrieved it to use as the basis of a new message.

So there's nothing I can find specific to saving and using a large file as a template.

@Matt Just to note the client only referenced the number of characters rather than the file size. That is I think he is saying that an email could have a 1mb image/attachement and download without a problem, but if the number of characters in the email is more than a set amount it won't render (or possibly won't render it all).

In regards to, "Now thee might be some limit to the inline CSS, but I have never heard anything." The inline css (where there are a lot of in modern responsive templates these days) would count towards that character count. So if there is any limit on the the character count of the inline css, I think that is what the client is getting at. I've never heard of any such limit but if there is for Thunderbird I'd be very interested in hearing about that. Otherwise, I'll pass on the info that there is no known limit on the character count of a template/email to be downloaded to Thunderbird. Thanks!

Zenos said

A glance at the "size" column (which I don't normally have enable"ld) in one of my folders indicates that received messages frequently exceed your 50 KB limit.

Amen to that. I get a crappy email from twitter every day (they want me to sign back in) that is some 80Kb without the remote graphics.

@Zenos

Thanks for your response. I assume your 237 KB email has more than 50 thousand characters and has downloaded fine to your thunderbird account. I don't personally have thunderbird so glad you have been able to confirm there is no thunderbird imposed limit on the number of characters in an email/email template code, whether it be code for tables, header styles, inline styles, or regular written text.

And that if the client is experiencing any such limitations it is not being set by Thunderbird. Thank you!

Just to add for others who come across this thread. It appears Thunderbird does have settings that allow you to set how large a template size can be and anything over that will be truncated.

Tools > Account Settings > Disk Space

So if a user sets that to 65KB, than it's possible that a message over 50 or so thousand characters could get truncated it sounds like. This doesn't appear to be a default setting, but may explain what the client was referring to.

Also it appears gmail will trim/truncate any message that has a template code over 102KB. That is, not the attachment size or images hosted on external servers, but the code in the actual template.. if it exceeds 102KB it will be truncated. So if a template is 102KB which I imagine is maybe 60 to 80 thousand characters it would be truncated and presumably it would be truncated then in whichever email client a person uses such as Thundermail, Mail.App, Outlook etc.

So while the client may have been confusing character count for template file size, since character counts and KB are relatively closely related I can see what they may be getting at.

I'll let them know as long as the user doesn't change their email size truncating setting, and as long as in the case of gmail at least the template isn't more than 102KB, it will download without a problem.

Thanks everyone!

The setting I can see sets a limit for download, i.e. from a mail server. This setting is for those with restricted or expensive bandwidth, or exceedingly modest local storage capacity. I don't imagine you would be loading templates that way (is that how you get a template, via email? Not downloaded via the browser?), so I don't see this is necessarily a limit for creation of your newsletters. But yes, your intended recipients would probably not get your messages with this setting at 50 KB in their own clients. Nor would they get much else, so I'd take it they were exercising their preference not to have their Thunderbird mailbox full of sales pitches and other commercial matter. (That wouldn't stop these things from clogging up the mailbox on the server, though.)

As I commented before, and Matt has confirmed, 50 KB would be a very restrictive setting with the rich content commonly found in commercial email messages these days.

I continue to be amused at your concern with the size of the template. Is the added matter (i.e. your actual communication with your correspondent) really so insignificant that it is swamped by all the template material, presumably markup, graphics, layout, webbugs and javascripts? Bear in mind that Thunderbird does not run javascript embedded into messages, so some of your more ambitious content may not render as you wish for your correspondents who read their email in Thunderbird.

My message was created by selecting all the text on this web page and pasting and re-pasting until my editor (Notepad++) reported 100 KB "length". This value increments by one for each letter I type so may represent characters, but if you were using wide (multi-byte) utf-8 characters, you'd probably clock up more bytes than characters.

In Thunderbird, the received message doubled up again because there would have been some overhead HTML coding and the message body repeated as plain text.

Zenos,

Yes, the setting appears to relate to downloading a message to ones computer. That is when I use an local mail application such as Apple Mail, Outlook, Thunderbird, etc, that message/email/email template (whichever word your prefer to use), is downloaded to ones computer in that app from the person's email server / imap server / pop server / exchange server.

That's correct, the setting is for people with limited bandwidth presumably. So someone who does set it relatively low, would potentially have their messages truncated which I see a lot of threads in google on for Thunderbird, and could explain what the client was referring to.

In regards to you being continually amused by my concern for the size of the template, you may have missed the several times I mentioned it but will mention again just incase. I personally am not considered at all about the size of email or the number of characters and have never heard of any such limitations for users prior. However as noted a client has mentioned it, and rather than telling them I'm amused by their question, I wanted to due my due dilligence and check with the Thunderbird team to verify for sure that there is no validity to it. Or to perhaps uncover information which may explain why they thought that was the case.

In regards to javascript, I'm not sure where that is coming from as to my knowledge I have never mentioned anything about javascript in the email templates. The templates created by MailChimp are sent more than 600 million times a day so I"m not aware of any "webbugs" you are referring to either. Yes the templates include a couple images (hosted on mailchimp server), and of course layout code, and text content, and then all the required inline and head styles required to make the emails responsive.

While the intial responses I got here implied the client's information as completely incorrect, I have since determined through my own research that it is possible that messages are truncated if the user manually sets a limit under settings. Also if the user pulls in their mail from a gmail server it appears if the template code is more than 102KB the message will be truncated. I'm not sure if that truncation only occurs at gmail.com or if also applies to emails recieved at gmail and then opened in thunderbird or outlook for instance. In either case I was never aware of that 102KB gmail limit or if other email clients have one as well they may be higher or lower. In any case that information could also help explain what the client was originally referring to.

The first thing I told the client was that the templates are a standard kb site used by millions and not aware of any wide spread truncation issue, but once again wanted to verify any validity to the statement. Through my research I believed I have enough info for a complete response to them.

Thank you.