Add mutation observer example to Azure AD B2C Javascript Docs

[jamescrowley]

The documentation mentions mutation observers in passing but doesn't explain why or give an example of how to use them.

We probably need confirmation from the team that what I'm proposing here is considered 'supported' but this is the only way I have found to ensure we can access DOM elements that Azure AD B2C has added to the document.

[prmerger-automator]

@jamescrowley : Thanks for your contribution! The author(s) have been notified to review your proposed change.

[learn-build-service-prod]

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[ttorble]

@garrodonnell

Can you review the proposed changes?

IMPORTANT: When the changes are ready for publication, adding a #sign-off comment is the best way to signal that the PR is ready for the review team to merge.

#label:"aq-pr-triaged"
@MicrosoftDocs/public-repo-pr-review-team

[garrodonnell]

Thanks for your contribution @jamescrowley. Let me discuss this with the team to get a technical review and come back to you on it.

[v-ccolin]

I sent an email to the content owner today.

@MicrosoftDocs/public-repo-pr-review-team

[v-dirichards]

I sent a Teams message to the content owner today.

@MicrosoftDocs/public-repo-pr-review-team

[v-dirichards]

From the article's author:

[v-ccolin]

I sent an email to the content owner today.

@MicrosoftDocs/public-repo-pr-review-team

[v-dirichards]

I sent a Teams message to the content owner today.

@MicrosoftDocs/public-repo-pr-review-team

[ttorble]

I sent email to the content owner today.

@MicrosoftDocs/public-repo-pr-review-team

[Copilot]

Pull Request Overview

This PR enhances the Azure AD B2C JavaScript documentation by adding a practical example of using mutation observers to interact with dynamically added DOM elements. The documentation previously mentioned mutation observers in passing but lacked concrete implementation guidance.

• Removes an overly long sentence that briefly mentioned mutation observers
• Adds a comprehensive explanation and code example demonstrating how to use mutation observers
• Provides practical guidance for developers who need to manipulate elements that Azure AD B2C adds dynamically

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[Copilot]

There is an extra space in 'the DOMContentLoaded' - should be 'the DOMContentLoaded'.

Suggested change

	In either case, you may use inline scripts or an external script. If you wish to manipulate elements that Azure AD B2C dynamically adds to the template, you will need to use a mutation observer, as the elements will not be available when using deferred javascript execution or waiting for the DOMContentLoaded event.
	In either case, you may use inline scripts or an external script. If you wish to manipulate elements that Azure AD B2C dynamically adds to the template, you will need to use a mutation observer, as the elements will not be available when using deferred javascript execution or waiting for the DOMContentLoaded event.