RequireJS resolver sometimes fails to detect blocked resources

[ishakhsuvarov]

Preconditions (*)

1. Magento 2.3.5-p1. Most likely any recent release would be affected.

Steps to reproduce (*)

1. Create a custom RequireJS config which defines a component complete with its url and fallback path. For example:

var config = {
    paths: {
        a: ['https://example.com/advertisement.js', 'Custom_Module/js/noop']
    }
};

2. Include this component on Checkout (may be reproducible elsewhere)

<!-- Something simple like this would work: -->
<script type="text/x-magento-init">
    {
        "*": {
            "a": {}
        }
    }
</script>

3. Use a browser with any aggressive Ad Blocker extension which would block the required url
4. Open Checkout page

Expected result (*)

1. ✅ Ad Blocker extension blocks the script download from the url stated in RequireJS config (https://example.com/advertisement.js)
2. ✅ Checkout page loads and renders just fine

Actual result (*)

1. ✅ Ad Blocker Extension blocks script download from the original url
2. ℹ️ RequireJS uses path fallback mechanism to load a resource from second url, therefore not triggering an error.
3. ℹ️ Magento's RequireJS resolver cannot keep track of such events and continues to wait for original resource to load (as no error was produced), therefore not calling any of the callbacks.
4. ❌ Checkout page is displaying 2 spinning loaders and a fully rendered page under it as resolver does not track components which were loaded via fallbacks.

[m2-assistant]

Hi @ishakhsuvarov. Thank you for your report.
To help us process this issue please make sure that you provided the following information:

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

Please make sure that the issue is reproducible on the vanilla Magento instance following Steps to reproduce. To deploy vanilla Magento instance on our environment, please, add a comment to the issue:

@magento give me 2.4-develop instance - upcoming 2.4.x release

For more details, please, review the Magento Contributor Assistant documentation.

@ishakhsuvarov do you confirm that you were able to reproduce the issue on vanilla Magento instance following steps to reproduce?

• yes
• no

---

• Join Magento Community Engineering Slack and ask your questions in #github channel.

[magento-engcom-team]

@VladimirZaets Thank you for verifying the issue.

Unfortunately, not enough information was provided to acknowledge ticket. Please consider adding the following:

• Add "Reproduced on " label(s) to this ticket based on verification result

Once all required information is added, please add label "Issue: Confirmed" again.
Thanks!

[magento-engcom-team]

✅ Confirmed by @VladimirZaets
Thank you for verifying the issue. Based on the provided information internal tickets MC-34099 were created

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

[hostep]

@ishakhsuvarov: out of curiosity: is this regarding the checkout no longer working on the Magento Marketplace when uBlock Origin is active?

[ishakhsuvarov]

@hostep sorry for the delay. Yes, this is exactly that issue which started as your report on slack :)

Thank you for your participation!

[engcom-Charlie]

Hi @ishakhsuvarov we are not able to reproduce this issue on the latest 2.4-develop branch by provided steps.
Could you please take a look?
Thank you.

[magento-engcom-team]

Hi @ishakhsuvarov. Thank you for your report.
The issue has been fixed in #28117 by @ishakhsuvarov in 2.4-develop branch
Related commit(s):

• 303bd64e3c1a7281be08d3b73feb995ef580e61d
• bfdde51e16e4be105d92463ba4c481a4eb8dd363
• c1f132bd07cee811a7f876bcce2eb1fba5dd98ed
• 8602befa58ccd0c215aaa48b1023ca3d2ef07ac6
• 375b129374fb83ba4993c67cb893835da91032ec

The fix will be available with the upcoming 2.4.2 release.

[rav-redchamps]

Hey @ishakhsuvarov,

The changes in your pull request #28117 is causing issue with admin ui component grids.

Steps to reproduce:

1. Login to admin panel & navigate to Catalog > Products grid
2. Filter grid by some SKU
3. Close the browser window
4. Open admin panel in new private/incognito window
5. Go to Catalog > Product Grids

Expected result (*)

✅ Grid should be filtered by SKU

Actual result (*)

ℹ️ You will see that grid has SKU filter applied but it still show all the records

[hostep]

@rav-redchamps: could you open a new issue describing this issue and link to that PR? That will make sure the issue is being followed up, commenting on closed issues often doesn't seem to help here.

[rav-redchamps]

@hostep Done ✅ #33620