[BUG] New fix for rare title intersection observer bug

[kodeaben]

• I have written a good issue
  The PR Fix rare title intersection observer bug #2822 was reverted in pr (Revert "[KirbyPage] Fix rare title intersection observer bug (#2822)" #2912), due to a new bug being introduced by it ([BUG] Interaction with UI causes Page title to "flicker" #2911).

This means that the bug in #2822 has been reintroduced.

This issue is made to have #2822 fixed, without reintroducing the bug described in #2911

Describe the bug

Describe how to reproduce the bug

Which Kirby version was used?

What was the expected behavior?

Add any screenshots

Please complete the following information:

• OS: [e.g. Windows, MacOS, iOS]
• Browser [e.g. Chrome, Safari]
• Browser version [e.g. 22]

Are there any additional context?

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Checklist:

The following tasks should be carried out in sequence in order to follow the process of contributing correctly.

Verification

To make sure the bug is not intended behaviour; it should be verified by a member of team Kirby before moving on to implementation.

• Make sure the NOT verified label has been removed by a member of team Kirby; do not proceed until this is done

Implementation

The contributor who wants to implement this issue should:

• Make sure you have read: "Before you get coding".
• Signal to others you are working on the issue by assigning yourself.
• Create a branch from the develop branch following our branch naming convention.
• Create a test that reproduces the bug following guidelines in: "The good: Test".
• Write code to fix the bug

Review

Once the issue has been implemented and is ready for review:

• Do a self-review.
• Create a pull-request.

[RasmusKjeldgaard]

No longer an issue, please reopen if it occurs again