Hi @engcom-Hotel. Thank you for working on this issue.
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Hello @rogerdz,

Thanks for the report and collaboration!

To speed up the processing of this issue, please provide us with the following information:

• Summary of the issue
• Information on your environment
• Steps to reproduce
• Expected and actual results

Thanks

Hi @engcom-Hotel, I update:

• Summary of the issue:
  Only execute js with element display in viewport
  Only trigger binding with element display in viewport
  Add event mousemove for execute for another js

• Information on your environment:
  magento 2.4-develop

• Steps to reproduce:
  Open inspect in browser (press f12), select tab network.
  Load site without any action same 'touchstart', 'mouseover', 'wheel', 'scroll', 'keydown' actions.
  Check the number of requests, only javascript related to the element in viewport is loaded.
  Scroll mouse and you will see the remaining javascript loaded.
  Check performance in lighthouse

• Expected results:
  Number of requests reduced 20-30rq when loading page
  Total Blocking Time reduced 20-30ms on Lighthouse
  JavaScript execution time reduced 1s on Lighthouse

Hello @rogerdz,
Thanks for the detailed steps!

The issue is not reproducible for us.

We have compared the instances with and without PR changes, but the performance seems degrading. Please have a look at the below screenshots for reference:

Without PR changes:

With PR Changes:

Please let us know if we have missed anything.

Thanks

Dear @rogerdz,

We've observed that there haven't been any updates on this issue for quite some time. Therefore, we're assuming it's been resolved and will be closing it. Feel free to open a new ticket or reopen this one if you require further assistance.

Regards

Hello @rogerdz,

We have retested this issue, please refer to this #39132 (comment).

Thanks

Hi @rogerdz,

This issue is being closed since it has not been updated in a long time.Please feel free to reopen or raise a new ticket if the issue still exists.

Thanks.