[Issue] Fix URL path of Sourcemap(.map) files

[m2-assistant]

This issue is automatically created based on existing pull request: #28415: Fix URL path of Sourcemap(.map) files

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Description (*)

Verified the problem and fix on Magento 2.4.5-p1 and 2.4-develop. The problem doesn't exist on Magento 2.3.7-p4 so probably one of the recent changes in 2.4.x to the grunt code or one of the updated npm packages causes the problem.

Steps to reproduce:

1. Setup clean Magento
2. Copy package.json.sample to package.json
3. Run npm install
4. Run cp Gruntfile.js.sample Gruntfile.js
5. Run grunt exec:luma
6. Run grunt less:luma
7. Run: grep -r 'sourceMappingURL' pub/static and notice this output:

$ grep -r 'sourceMappingURL' pub/static
pub/static/frontend/Magento/luma/en_US/css/styles-l.css:/*# sourceMappingURL=pub/static/frontend/Magento/luma/en_US/css/styles-l.css.map */
pub/static/frontend/Magento/luma/en_US/css/styles-m.css:/*# sourceMappingURL=pub/static/frontend/Magento/luma/en_US/css/styles-m.css.map */

Which are incorrect paths to the sourcemap files, the browser tries to load these incorrectly resulting in 404 errors and doesn't find the original less files in the inspector:

Related Pull Requests

Fixed Issues (if relevant)

1. Fixes magento/magento2#<issue_number>

Manual testing scenarios (*)

1. ...
2. ...

Questions or comments

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 @engcom-Hotel. Thank you for working on this issue.
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[engcom-Hotel]

Hello @tshabatyn,

Thanks for raising the PR!

@hostep Thanks for the reproduction steps!

We have tried to reproduce the issue with mentioned steps and the issue is reproducible for us. Please find below the screenshot for the same:

Hence confirming the issue.

Thanks

[github-jira-sync-bot]

✅ Jira issue https://jira.corp.adobe.com/browse/AC-8522 is successfully created for this GitHub issue.

[m2-assistant]

✅ Confirmed by @engcom-Hotel. Thank you for verifying the issue.
Issue Available: @engcom-Hotel, You will be automatically unassigned. Contributors/Maintainers can claim this issue to continue. To reclaim and continue work, reassign the ticket to yourself.