[Issue] add sourceMap generation for less files in developer mode

[m2-assistant[bot]]

This issue is automatically created based on existing pull request: magento/magento2#38977: add sourceMap generation for less files in developer mode

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Description (*)

Currently when running magento 2 in developer mode with server-side less compilation it's very hard to detect where a style is coming from. The only workaround is to use Grunt. However the underlying library for less compilation supports sourcemap generation with a flag that can be toggled based on the mode magento is in.

Related Pull Requests

Fixed Issues (if relevant)

Manual testing scenarios (*)

1. Switch magento 2 in developer mode
2. Let it regenerate css from the less files
3. Check inspector to see the source file responsible for the code

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)
• [ ] README.md files for modified modules are updated and included in the pull request if any README.md predefined sections require an update
• [ ] All automated tests passed successfully (all builds are green)

[engcom-Hotel]

Hello @ioweb-gr,

Thanks for the report and collaboration!

We are confirming this issue for further processing.

Thanks

[m2-assistant[bot]]

Hi @engcom-Hotel. 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: :point_down:

• [ ] 1. Verify that issue has all the required information. (Preconditions, Steps to reproduce, Expected result, Actual result).
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[github-jira-sync-bot]

:white_check_mark: Jira issue https://jira.corp.adobe.com/browse/AC-12650 is successfully created for this GitHub issue.

[m2-assistant[bot]]

:white_check_mark: 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.