RuntimeError: unreachable executed as soon as extension is loaded

[BafDyce]

I create the extension with make packed.zip but when I load it in my browser and open a site on which it should be executed, I get the following error:

RuntimeError: unreachable executed macro_railroad_ext.js line 36 > WebAssembly.compile:1667270:1

System information:

• Firefox: v93.0
• OS: Linux
• rustc 1.56.0 (09c42c458 2021-10-18)
• cargo 1.56.0 (4ed5d137b 2021-10-04)
• cargo web 0.6.26

I think it has to do with calling the DOM api or something. For example, the following code does not result in this error:

#[cfg_attr(cargo_web, js_export)]
pub fn load() {
    let x = 1+1;

    /*if let Err(err) = priv_load() {
        stdweb::console!(error, format!("{:?}", err))
    }*/
}

However, the following results in the error:

#[cfg_attr(cargo_web, js_export)]
pub fn load() {
    let x = 1+1;
    stdweb::console!(error, "asdf");

    /*if let Err(err) = priv_load() {
        stdweb::console!(error, format!("{:?}", err))
    }*/
}