PR Checklist

• The commit message follows our guidelines: https://github.com/elementor/elementor/blob/master/.github/CONTRIBUTING.md

PR Type

What kind of change does this PR introduce?

• Bugfix
• Feature
• Code style update (formatting, local variables)
• Refactoring (no functional changes, no api changes)
• Build related changes
• CI related changes
• Documentation content changes
• Other... Please describe:

Summary

Renamed internal setting of _cssId to _element_id.

Description

An explanation of what is done in this PR

Test instructions

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Quality assurance

• I have tested this code to the best of my abilities
• I have added unittests to verify the code works as intended
• Docs have been added / updated (for bug fixes / features)

Fixes #