In a browser, set the clipboard (WASM)

cargo.toml

[package]
name = "set-web-clipboard"
version = "0.1.0"
edition = "2021"

[dependencies]
# JavaScript in Rust
wasm-bindgen = "0.2" # May not be needed
web-sys = { version = "0.3", features = ["Clipboard"] }

main.rs

//! Reference: <https://docs.rs/web-sys/0.3.57/web_sys/struct.Clipboard.html>

#[cfg(web_sys_unstable_apis)]
fn set_clipboard(text: String) {
    use wasm_bindgen::prelude::*;

    #[wasm_bindgen]
    extern "C" {
        #[wasm_bindgen(js_namespace = ["navigator", "clipboard"])]
        fn writeText(s: &str);
    }

    writeText(text.as_str());
}
#[cfg(not(web_sys_unstable_apis))]
fn set_clipboard(text: String) {
    // This is an unstable Web API. This package needs to be compiled as such.
    console::log("Package compiled without unstable APIs.");
}

Thanks to the Yew community for helping with this, quickly and politely. I couldn't find a straightforward solution, so I created this Gist for others.

Feel free to leave comments to anyone with questions.