[Issue] Avoid binding magnifier events in duplicate on resize

[m2-assistant]

This issue is automatically created based on existing pull request: #30695: Avoid binding magnifier events in duplicate on resize

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Description

A browser resize event will trigger the magnifier to be re-initialised. This includes binding a fresh set of event listeners to the image so that the magnifier will show as expected (on click or hover). However, there is no mechanism to unbind the old event listeners, so each time the browser triggers a resize event these will stack.
This is made worse by the 'hover' event type triggering the 'mouseover' event immediately after adding a listener for the same. This means that each resize event will consume progressively more CPU, without any additional value.

Related Pull Requests

None

Fixed Issues

None

Manual testing scenarios

1. Visit a product page with magnifier in use and configured for hover events
2. Observe the resting CPU usage of the page
3. Resize the viewport (either height or width)
4. Observe a spike in CPU usage, which subsides
5. Resize the viewport several times
6. Observe a progressively longer spike in CPU usage
7. Continue resizing the viewport and notice that CPU eventually (after ~8 resizes in my experience) caps out at 100% for an unacceptable amount of time (several minutes), rendering the page useless.

Before & after pictures from JavaScript profiler

Before:

After:

Questions or comments

None

Contribution checklist

• Pull request has a meaningful description of its purpose
• All commits are accompanied by meaningful commit messages
• All new or changed code is covered with unit/integration tests (if applicable)
• All automated tests passed successfully (all builds are green)

[m2-assistant]

Hi @krishprakash. Thank you for working on this issue.
In order to make sure that issue has enough information and ready for development, please read and check the following instruction: 👇

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[magento-engcom-team]

✅ Confirmed by @krishprakash
Thank you for verifying the issue. Based on the provided information internal tickets MC-38922 were created

Issue Available: @krishprakash, You will be automatically unassigned. Contributors/Maintainers can claim this issue to continue. To reclaim and continue work, reassign the ticket to yourself.

[m2-assistant]

Hi @engcom-Oscar. Thank you for working on this issue.
Looks like this issue is already verified and confirmed. But if you want to validate it one more time, please, go though the following instruction:

• 1. Add/Edit Component: XXXXX label(s) to the ticket, indicating the components it may be related to.
• 2. Verify that the issue is reproducible on 2.4-develop branch
     Details

     - Add the comment @magento give me 2.4-develop instance to deploy test instance on Magento infrastructure.
     - If the issue is reproducible on 2.4-develop branch, please, add the label Reproduced on 2.4.x.
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[gabrieldagama]

Hi @m2-assistant[bot]. Thank you for your report.
The issue has been fixed in #30695 by @fredden in 2.4-develop branch
Related commit(s):

• 6bec772fd1e204b758c9ad27d596e53238888624
• 693e366eb9a60d3fdfe0c426277524270302e3f2
• 2bb781f0961e92520a2f6c550b893246d24a77ae

The fix will be available with the upcoming 2.4.3 release.