Type: LanguageService
In 0.24.0-insiders, there are some themes rendering the syntax highlighting incorrectly. if this affects your theme, please add a comment to this issue. We are working out which ones were broken with our syntax highlighting change.
To disable the new syntax highlighting, set "C_Cpp.enhancedColorization": "Disabled" and you will get the old behavior again.
Known themes with this issue:
Affects the Monokai theme.
"C_Cpp.enhancedColorization": "Disabled" resolved it.
This is affecting the Atom One Dark when using "editor.renderWhitespace": "all".
The white spaces inside a comment are highlighted in the same color as words, for example:

"C_Cpp.enhancedColorization": "Disabled" resolved it as well.
Also affects the vscode-ayu themes, example below. Of course disabling the mentioned option fixes the issue.

@Pigzaum
Whitespace character rendering in comments has wrong colors also in the default theme:

I believe it should have the same color as everywhere else.
Furthermore, changing the color with:
"workbench.colorCustomizations": {
"editorWhitespace.foreground": "#ffffff22"
},
does not affect the comments.
The same problem occurs with strings:

Again, the whitespaces are orange instead of gray.
Please upvote the following issue: https://github.com/microsoft/vscode/issues/49462
One potential "fix" for the the editor.renderWhitespace issue is:
Fixed with 0.24.0-insiders2. Set the "C_Cpp.updateChannel" setting to "Insiders" to auto-install it.