Missing JS file (critical-css-loader) in Magento 2.3.4

[Sathishkumar8731]

Preconditions (*)

1. Magento 2.3.4
2. MYSQL 5.6
3. PHP 7.2.X

Steps to reproduce (*)

1. Go to the File Path: app/code/Magento/Theme/view/frontend/requirejs-config.js
2. Open the "requirejs-config.js" file and you can find below code in Mapper section

'criticalCssLoader': 'Magento_Theme/js/view/critical-css-loader',

3. Whereas, critical-css-loader js file should be available in the file path: app/code/Magento/Theme/view/frontend/web/js/view

Expected result (*)

1. Loader should need to show while calling criticalcss

Actual result (*)

1. Loader is not working and unable to customize it on Custom them.

[m2-assistant]

Hi @Sathishkumar8731. Thank you for your report.
To help us process this issue please make sure that you provided the following information:

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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

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@Sathishkumar8731 do you confirm that you were able to reproduce the issue on vanilla Magento instance following steps to reproduce?

• yes
• no

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[m2-assistant]

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[magento-engcom-team]

✅ Confirmed by @engcom-Bravo
Thank you for verifying the issue. Based on the provided information internal tickets MC-32088 were created

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

[magento-engcom-team]

Hi @Sathishkumar8731. Thank you for your report.
The issue has been fixed in #26987 by @mrtuvn in 2.4-develop branch
Related commit(s):

• e2c403fa3d9fcaa2341214218e35889b4e83b0b8
• eee02627f468d04d24530ddde87ad30f02cee15e
• befbca488671ea50343801ee1232bef4ee066e22
• e22c47c6dce745162a5df8a88873f7f08fb8e290
• a3218fe7b4b8479f1e4ce2d1d5180a80e3245f12
• f98537d818f4dd894a7ba36ef3d56c5865d65ac1
• 339c099c79b183c0a8caca37e2caa8b60d276a49
• 5843df461626ac32230c2425d07f60b480637333
• abad8db69e9b66d8b32be10d38e283c09ebd2d72
• c40d35c9d1de2d1896e2c9a19c18435d2145c5d5
• fb839e740c986c7f52469a566b368eb8bf80e8f3
• e45dd6ee71abfb7b445021281808d86d199cd550
• 5c29e1998e399696046e8562f8ec1a43bfd2ab42

The fix will be available with the upcoming 2.4.0 release.

[patruvlad]

@magento-engcom-team I checked the commits from the pull request , this issue is not fixed, Critical CSS should have a loader when activated and in the commits the only thing that happens is that the js needed for that loader is removed from requirejs-config when the file itself should be added for the loader to work