Expand macro recursively does not work on macro in `cfg_attr` attribute, despite the feature being enabled for r-a

I have a type that is roughly like this:

#[derive(Clone, Debug)]
#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
pub struct Foo(String, Option<usize>);

If I place my cursor on Clone or Debug and execute the "Rust Analyzer: Expand macro recursively" command in VS Code, I get the expected expanded macro output. However, if I place it on Serialize or Deserialize, I get "Not available" as the output, despite these macros being active due to my Rust analyzer settings:

{
    "rust-analyzer.cargo.features": "all",
    "rust-analyzer.checkOnSave.features": "all"
}

If I change my code to

#[derive(Clone, Debug, serde::Serialize, serde::Deserialize)]
pub struct Foo(String, Option<usize>);

I can expand the macros, but I don't see why they can't also be expanded behind the feature gate when that feature is activated.

rust-analyzer version: rust-analyzer version: 0.3.1131-standalone (897a7ec4b 2022-07-17)

rustc version: rustc 1.62.0 (a8314ef7d 2022-06-27)

relevant settings: I think the relevant settings are already put above.

Reproduce the issue in VS Code with the shown cfg_attr derive and all features enabled, then trace rust-analyzer's recursive macro expansion handling for attribute-gated derives. Done means Serialize and Deserialize expand successfully behind cfg_attr, matching the behavior of direct derives.