Tabs and Line-Highlight

[CSP02]

Added two new features:

1. Tabs system where you can embed two or more code into a single wrapper.
2. Line-highlight where you can highlight a specific line.
3. Fixed most of the bugs and optimised whole code, optimised CSS, and removed most of the unwanted code in JS files.

Full Changelog: v3.5.8...v4.0.0

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This discussion was created from the release Tabs and Line-Highlight.