Support space as seperator between language and additional class in code block

[tuyen-at-work]

Use case

Let say I want to add h500 as a class for a code block.

Editor

In VS Code, we can use space between language and additional class without loose syntax highlighting:

But if I use comma instead of space between language and additional class, the highlighting doesn't work:

Render

Let check what happen when two above code blocks got rendered:

The first case loose syntax highlighting:

The second case work nicely:

Current status

In current situation, if I want to use additional class, I have to choose:

• Either have syntax highlighting in VS Code, and loose it when rendered, or
• Don't have syntax highlighting in VS Code, and get it when rendered

Feature request

Please support space as seperator between language and additional class in code block, so we can have syntax highlighting for both editor and rendered version.

[ehuss]

This should be fixed by #1469.