Disable selection for highlight meta

[stevenjoezhang]

PR Checklist

Please check if your PR fulfills the following requirements:

• The commit message follows our guidelines.
• Tests for the changes was maked (for bug fixes / features).
  • Muse | Mist have been tested.
  • Pisces | Gemini have been tested.
• Docs in NexT website have been added / updated (for features).

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:

What is the current behavior?

Issue resolved: #448

What is the new behavior?

• Screenshots with this changes: N/A
• Link to demo site with this changes: N/A

How to use?

In NexT _config.yml:

...

Does this PR introduce a breaking change?

• Yes.
• No.

[1v9]

And codeblock.copy_button still copy meta, maybe add an option or do something like refactoring dimmer by you before --- don't give choice to users 😉

[stevenjoezhang]

Relevant issue #1110

[stevenjoezhang]

Reverted in next-theme/hexo-theme-next@9fdaba2

markdownlint recommends that don't use dollar signs before commands without showing output.

https://github.com/DavidAnson/markdownlint/blob/main/doc/md014.md