Bei Zhang - Ikarienator

@Kixiron This is only reproducible using `--release` with the `serialize` feature: ``` cargo build --release --features serialize ``` My environment is `cargo 1.51.0 (43b129a20 2021-03-16)` and `rustc 1.51.0 (2fd73fabe 2021-03-23)`.

Ah that was fast. I had a simpler fix by writing down the type of `strings` as `Vec`. Your fix is probably better.

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