TYPO3: Form properties.fluidAdditionalAttributes.placeholder translation - forms

Question

I'm working on translating my Typo3 page.
Now I've come to my contact form which I want to translate. From the Typo3 Documentation I've found that I need something like this:
contact.element.subject.properties.fluidAdditionalAttributes.placeholder
...as the translation ID inside my locallang.xlf file. I've linked my CustomFormSettings.yaml via TypoeScript, in there set the translation path to my extension and created a contact form.
I was actually able to translate the submit button for example and other buttons. But I can't get the placeholder inside my contact form to get translated, they all fallback to the value set in the contact form not the translation.
I'm guessing I'm handling the fluidAdditionalAttributes property wrong but I've tested lots of other combinations then the above.
What is the exact line I have to type inside my translation ID?
Here is my complete contact form:
renderingOptions:
submitButtonLabel: Submit
identifier: contact
label: Contact
type: Form
prototypeName: frameform
finishers:
-
options:
subject: 'Your message: {subject}'
recipientAddress: mail#mail.com
recipientName: 'Recipient Name'
senderAddress: '{email}'
senderName: '{name}'
replyToAddress: ''
carbonCopyAddress: ''
blindCarbonCopyAddress: ''
format: html
attachUploads: true
translation:
language: ''
identifier: EmailToReceiver
-
options:
subject: 'We have received: {subject}'
recipientAddress: '{email}'
recipientName: '{name}'
senderAddress: mail#mail.com
senderName: 'Sender Name'
replyToAddress: ''
carbonCopyAddress: ''
blindCarbonCopyAddress: ''
format: html
attachUploads: true
identifier: EmailToSender
-
options:
pageUid: '7'
additionalParameters: ''
identifier: Redirect
renderables:
-
renderingOptions:
previousButtonLabel: 'Previous step'
nextButtonLabel: 'Next step'
identifier: mainPage
type: Page
renderables:
-
defaultValue: ''
identifier: name
label: Name
type: Text
properties:
fluidAdditionalAttributes:
placeholder: Name
required: required
validators:
-
identifier: NotEmpty
-
defaultValue: ''
identifier: subject
label: Subject
type: Text
properties:
fluidAdditionalAttributes:
placeholder: Subject
required: required
validators:
-
identifier: NotEmpty
-
defaultValue: ''
identifier: email
label: Email
type: Text
properties:
fluidAdditionalAttributes:
placeholder: 'Email address'
required: required
validators:
-
identifier: NotEmpty
-
identifier: EmailAddress
-
defaultValue: ''
identifier: message
label: Message
type: Textarea
properties:
fluidAdditionalAttributes:
placeholder: Message
required: required
minlength: '10'
maxlength: '512'
validators:
-
identifier: NotEmpty
-
options:
minimum: '10'
maximum: '512'
identifier: StringLength
-
renderingOptions:
previousButtonLabel: 'Previous step'
nextButtonLabel: 'Next step'
identifier: summarypage
label: 'Summary page'
type: SummaryPage

Answer 1

You can override your placeholders in a locallang.xlf like this: element.<field-identifier>.properties.placeholder
example:
<trans-unit id="element.firstname.properties.placeholder">
<source>Your first name</source>
<target>Ihr Vorname</target>
</trans-unit>