Description
Running cargo +nightly doc
on a library crate and viewing the resulting documentation in Safari 17.2 on macOS Sonoma 14.2 results in all non-code text being bold, like so:

However, if cargo doc
is run on the same crate using Rust stable 1.74.1, the resulting docs are formatted correctly:

When the built-on-nightly docs are opened in Firefox or Chrome, the text is not bold. Recently-built docs on docs.rs are not bold in Safari at all.
Inspecting the web elements shows that Safari considers the text to have a font-weight of 400 (normal), so I'm guessing the problem is down to the selection of the font. However, this is where my web styling skills end.
Stable Rust version:
rustc --version --verbose
:
rustc 1.74.1 (a28077b28 2023-12-04)
binary: rustc
commit-hash: a28077b28a02b92985b3a3faecf92813155f1ea1
commit-date: 2023-12-04
host: x86_64-apple-darwin
release: 1.74.1
LLVM version: 17.0.4
Nightly Rust version:
rustc +nightly --version --verbose
:
rustc 1.76.0-nightly (445177724 2023-12-16)
binary: rustc
commit-hash: 445177724ac2beebf4faa5a3ffacb2adbe7e7846
commit-date: 2023-12-16
host: x86_64-apple-darwin
release: 1.76.0-nightly
LLVM version: 17.0.6
Crate used to build docs shown above: https://github.com/jwodder/strtoint (though the problem happens with every library crate I build docs for)