bug: Migration v0.28.3 to v.0.80.1 -- Custom class: self.page object has no setter

[NiTRoeSE]

Duplicate Check

• I have searched the opened issues and there are no duplicates

Describe the bug

Hello i try to migrate a big app with a lot of code from flet 0.28.3 to 0.80.1 and had the following issue:
To demonstrate i have created a simple example wich have exact the same behavior.
When i use the same class TestContent like in example in flet 0.80.1 the app throws the error self.page object has no setter

I´m a bit lost and wonder how i should write this stuff to work with flet 0.80.1 ?

Thanks in advanced!

Code sample

Code

##### working in flet 0.28.3

import flet as ft

class TestContent(ft.Container):
    def __init__(self, page:ft.Page):

        self.page = page
        super().__init__()
        
        self.content = ft.Column()
        self.content.controls.append(
            ft.Text(self.page.title)
        )


def main(page: ft.Page):

    page.title = "Test Content"
    content = TestContent(page)
    page.add(content)
    page.update()

ft.app(main)

To reproduce

Run code example in venv with flet 0.28.3 --> works.
Run code example in venv with flet 0.80.1 --> dont work.

Expected behavior

Should work in flet 0.80.1+

Screenshots / Videos

Captures

Operating System

macOS

Operating system details

26.0.1

Flet version

0.80.1

Regression

Yes, it used to work in a previous Flet version (please specify the version in additional details)

Suggestions

No response

Logs

Logs

[Paste your logs here]

Additional details

works in flet 0.28.3