Toggle property editor doesn't return initial state when true

[lumimario]

Which Umbraco version are you using? (Please write the exact version, example: 10.1.0)

15.1.1

Bug summary

When you configure the Toggle editor to have a default state of True, this is shown correctly in the backoffice, but in the frontend it returns False.

Specifics

No response

Steps to reproduce

Create a new data type based on the Toggle property editor. Configure the Initial State as On.
Create a new Document Type with Template and add a property that uses the new data type.
Create a new page based on the previous document type.
The toggle shows on by default in the backoffice.

Render the value of the page using @Model.Value("toggleProperty")
The value returned is False.

NOTE: if I turn the toggle off and back on and save the page, then the value returned is True.

Expected result / actual result

The returned value should be True.

[github-actions]

Hi there @lumimario!

Firstly, a big thank you for raising this issue. Every piece of feedback we receive helps us to make Umbraco better.

We really appreciate your patience while we wait for our team to have a look at this but we wanted to let you know that we see this and share with you the plan for what comes next.

• We'll assess whether this issue relates to something that has already been fixed in a later version of the release that it has been raised for.
• If it's a bug, is it related to a release that we are actively supporting or is it related to a release that's in the end-of-life or security-only phase?
• We'll replicate the issue to ensure that the problem is as described.
• We'll decide whether the behavior is an issue or if the behavior is intended.

We wish we could work with everyone directly and assess your issue immediately but we're in the fortunate position of having lots of contributions to work with and only a few humans who are able to do it. We are making progress though and in the meantime, we will keep you in the loop and let you know when we have any questions.

Thanks, from your friendly Umbraco GitHub bot 🤖 🙂

[NguyenThuyLan]

Thank you @lumimario for reporting this issue. I was able to reproduce it on v14.3.1 and v15.1.1
I see when calling the API to save content, the value of the toggle property editor was not sent along. Unless user clicks the toggle, the default value will not be sent with the API.