### HTML Button with Pre-filled Customer Data Example

Source: https://forma.tbank.ru/docs/online/setup-types/script/testing-script

An example demonstrating the `tinkoff-create-button` HTML custom element. It shows how to configure the button with specific `shopId`, `showcaseId`, `payment-data` (including `demoFlow`, `initialStage`, item details, promo code, and customer contact info), and `ui-data` to open in a new tab with pre-filled customer information for a demo application.

```HTML
<tinkoff-create-button
  size="M"
  subtext="от 3400 ₽ в месяц"
  shopId="test_online"
  showcaseId="test_online"
  payment-data="demoFlow=sms&initialStage=filling&items.0.name=Hasta&items.0.price=19626.15&items.0.quantity=1&items.1.name=Hasta&items.1.price=1444.50&items.1.quantity=1&items.2.name=Hasta&items.2.price=84.15&items.2.quantity=1&promoCode=installment_0_0_6_5,85&sum=21154.80&values.contact.fio.firstName=Иван&values.contact.fio.lastName=Петров&values.contact.mobilePhone=+7 (988) 777-66-55"
  ui-data="productType=installment&useReturnLinks=true&view=newTab"
></tinkoff-create-button>
```

--------------------------------

### Demo Application Testing Parameters

Source: https://forma.tbank.ru/docs/online/setup-types/script/testing-script

Detailed documentation for `demoFlow` and `initialStage` parameters used to simulate various scenarios within the demonstration application. These parameters control the type of demo flow (e.g., SMS signing, meeting) and the initial state of the application (e.g., data filling, waiting for offer).

```APIDOC
demoFlow: enum, required
  Type of demonstration application
  sms: buyer signs credit documents via SMS
  ses: buyer signs documents using Self ID technology
  appointment: buyer signs documents at a meeting with a bank representative
  appointment-reject: rejection at a meeting
  reject: rejection of installment or credit for the buyer

initialStage: enum, optional
  filling: buyer data entry
  wait-offer: waiting for decision
  offers-all: bank offers
  wait-offer-timeout: waiting period expired
  kvk-signing-sms: T-Bank SMS signing
  ses-documents: Self ID signing for new T-Bank clients
  appointment: appointment of a T-Bank representative
  mts-add-additional-info: filling in additional client data for MTS Bank
  mts-documents: SMS signing with document upload for MTS Bank clients
  mts-svyaznoy-appointment: MTS Bank meeting information
  otp-signing-sms: SMS signing for OTP Bank clients
  otp-documents: SMS signing with document upload for new MTS Bank clients
  rencredit-signing-sms: SMS signing for Renaissance Bank clients
  kvk-issued: issued in T-Bank
  mts-issued: issued in MTS Bank
  otp-issued: issued in OTP Bank
  canceled: application canceled
  rejected: application rejected
```

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