Sintax highlighting of ?Sized rust code is invalid

[sgued]

Bug Report

Environment

Zola version: 18.0

Expected Behavior

In a rust code block, in a template, ?Sized is valid and should be highlighted correctly.

Current Behavior

Step to reproduce

Build a site with syntax highlighting enable, and include the following valid rust code block:

pub struct Testing<T: ?Sized> {
    testing: T,
}

Workaround

This workaround fully disables highlighting of "invalid" code, so it may not be suitable for everyone.
Use css styles and add the following CSS, loaded after the syntax theme itself:

// Fix bad syntax highlighting of ?Sized
.z-invalid {
  color: inherit;
  background-color: inherit;
}

.z-illegal {
  color: inherit;
  background-color: inherit;
}

[Keats]

It's a known issue: #1787