Use VS Code's syntax highlighting in Markdown preview

[David-Else]

Issue Type: Bug

When I use "editor.semanticHighlighting.enabled": true, TypeScript looks great, but now the Markdown code looks bad in comparison. Please see the screenshot.

VS Code version: Code 1.42.1 (c47d83b, 2020-02-11T14:50:36.977Z)
OS version: Linux x64 4.18.0-147.5.1.el8_1.x86_64

System Info

Item	Value
CPUs	Intel(R) Core(TM) i7-4770S CPU @ 3.10GHz (8 x 3681)
GPU Status	2d_canvas: enabled flash_3d: enabled flash_stage3d: enabled flash_stage3d_baseline: enabled gpu_compositing: enabled metal: disabled_off multiple_raster_threads: enabled_on oop_rasterization: disabled_off protected_video_decode: unavailable_off rasterization: disabled_software skia_renderer: disabled_off surface_control: disabled_off surface_synchronization: enabled_on video_decode: unavailable_off viz_display_compositor: enabled_on viz_hit_test_surface_layer: disabled_off webgl: enabled webgl2: enabled
Load (avg)	1, 1, 0
Memory (System)	7.50GB (2.44GB free)
Process Argv	--no-sandbox --unity-launch /home/david/sites/Link to typing objects cheat-sheet.md
Screen Reader	no
VM	0%

Extensions (9)

Extension	Author (truncated)	Version
vscode-deno	axe	2.0.4
spellright	ban	3.0.50
vscode-eslint	dba	2.1.1
prettier-vscode	esb	3.20.0
shell-format	fox	7.0.1
debugger-for-chrome	msj	4.12.6
LiveServer	rit	5.6.1
shellcheck	tim	0.9.0
quokka-vscode	Wal	1.0.279

[mjbvz]

@aeschli The markdown extension needs a command or api to get the semantic highlighting colors in order to support this

[aeschli]

@mjbvz Assigning back to you as it's a feature request for markdown.
I created #91375 for the missing API to programmatically get semantic tokens.

[mjbvz]

See #56356 for api feature request to get colors as they appear in the editor

Try this extension to get closer to VS Code's highlighting (but still without semantic highlighting): https://marketplace.visualstudio.com/items?itemName=bierner.markdown-shiki

[David-Else]

@mjbvz I have been looking at bierner.markdown-shiki and it is great. Is there a way I can convert my MD to a PDF with this highlighting you know of? Cheers.

[Nirmal4G]

I would also request an option to switch between VSCode themes and other standard markdown themes like GitHub's, GitLabs's, NuGet's and other places where they render markdown in their own styling.

[Nirmal4G]

It would be nice to support diff+language syntax highlighting in Markdown preview too! I can't seem to find any good solutions for this anywhere. If someone had written a tool, please point me to it!

[znorman-harris]

Another place where this is very apparent: new languages added to VSCode don't have syntax highlighting by default in the markdown preview. Oddly enough, any code blocks added as markdown and displayed via hover help and a language server have the proper color/style to match the editor, but are lacking from the markdown preview.