417
Mo Validation Mo Problems
(lemmy.world)
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this post was submitted on 19 Jan 2026
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Jokes aside, I have been blocked many times by overzealous email validation. Yes, my email has a plus sign in it. This is allowed under RFC5322, so deal with it. It is better to have no validation at all than incorrect validation.
A plus sign? That's nothing, LOL
Quote:
Because of one smartass customer who insisted on doing exact RFC 822 validation, I implemented exactly that. And yes,
is one of the test cases for a valid addr-spec. See (or generate) some others at https://github.com/mormegil-cz/rfcemailvalidator
I like this issue in the form of a quiz
TIL:
🫱@🫲
is a valid e-mail address.
Nice, I was able to send an email to that.
I dont know if it's just me, but this comment is breaking the rendering of Voyager
I needed to use a code block for that address as several apps had a problem when I tested escaping the back ticks in the address for the inline code. Not sure if you mean that as it renders in it's own line or if anything else is broken
The best email validation is just sending an email to whatever provided by the user. If user receives an email and validates it, than its validated.
Email address spec is convoluted and this is indeed the best way. Noobs and ninja do it this way, normies try to validate before sending email
Email validation for a form should at most look for
Sending an email can take a few minutes. Form validation is instant.
Which would still not be perfect because "foo@bar", "foo@[123.123.123.123]" and "💩 @[IPv6 :::1]" are all technically valid email addresses.
It looks like the only validation that doesn't block something valid pretty much would start and end at "It has at least one @ symbol, and something on both sides".
So I can't be directly
bezos@aws?The worst sites are the ones that let you sign up with an unusual address but not log in. The worst I‘ve seen was some ticket system that rejected dfyx+theirdomain@mydomain after I clicked the link in their confirmation email.
There's an aspect of my surname which is somewhat unusual (at least in my country). As a result I occasionally get form validation errors when entering it. Sometimes those errors are extremely inscrutable. Sometimes a form validates but something elsewhere makes unvalidated assumptions about names which then breaks in completely unpredictable names...
Does it fall into one of the falsehoods programmers believe about names? https://www.kalzumeus.com/2010/06/17/falsehoods-programmers-believe-about-names/
Actually no. In fact, I think most people who thought for a minute would realise names like mine exist, it's just that sometimes people working systems don't think for a minute ;)
The number of scripts I've seen that would break with an O'Neill or O'Brien is too high. Worse is some people don't get it when pointed out.
Even worse is when they strip the plus sign out after the fact and then you can't log in anymore because you didn't realize that's what has happened.
This is criminal. You already send me a validation email, just check for an @ and leave me be
Yees this has happened to me before but with passwords. They have some length limit that they clamp to so you can't login after registering and I have to do a password reset right after signing up. Happened multiple times to me.
I had a website not let me enter a proton.me email address, when I changed it to my custom.fyi address, it worked fine. They wanted a three letter TLD.
No, I think they just blocked Proton email addresses. I've seen multiple services doing that.
That was my best customer support interaction ever. Company did not let me register with a "new" TLD email address, as "this is not a valid email address". I wrote them from that email address. They respondend to that email address with "this is not a valid address". I wrote back "how are we writing, then?" and never heard back 😂
Not sure if you also do aliases as well but I’ve seen an increase in websites flagging providers like addy.io as well. Extremely annoying that so many websites think they are so important that they refuse an alias.
I had a site refuse my email address for my .net domain. Like wtf, if it’s not .com it’s not a real email address? Idk what that was about.
@traxex
@ooterness
migadu has a cool workaround.
instead of:
alias+user@domain.tld
you give:
alias@user.domain.tld
then internally it transforms it to an alias when it comes in.
Same although for a totally different reason. There are some services that really don't like gtlds and they will say your address is invalid if it doesn't end in .com, .net, or .org...all my serious domains are gtld...so some services have emails on meme domains because the only domains I have with traditional tlds are memes