diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index df0038f9..27a324c2 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -403,6 +403,11 @@ jobs:
     - name: Use specific dependency versions for Rust 1.70 compatibility.
       run: |
         cargo update --package=once_cell --precise=1.20.3
+        # tempfile 3.27 pulled edition-2024 getrandom, which Cargo 1.70 can't parse.
+        cargo update --package=tempfile --precise=3.23.0
+        # js-sys 0.3.72 has no `std` feature, and later versions require a
+        # wasm-bindgen newer than the Rust 1.70 resolver would otherwise pick.
+        cargo update --package=js-sys --precise=0.3.80
         cargo update --package=uuid --precise=1.20.0
 
     # Don't use --all-features because some of the features have dependencies
@@ -421,7 +426,7 @@ jobs:
     - uses: ./.github/actions/install-rust
       with:
         toolchain: nightly
-    - run: cargo install cargo-fuzz --vers "^0.11"
+    - run: cargo install cargo-fuzz --version 0.13.2 --locked
     - run: cargo fetch
       working-directory: ./fuzz
     - run: cargo fuzz build --dev
diff --git a/cap-primitives/src/fs/manually/open.rs b/cap-primitives/src/fs/manually/open.rs
index 20a4b546..83129071 100644
--- a/cap-primitives/src/fs/manually/open.rs
+++ b/cap-primitives/src/fs/manually/open.rs
@@ -8,7 +8,6 @@ use crate::fs::{
 };
 #[cfg(any(target_os = "android", target_os = "linux", target_os = "freebsd"))]
 use rustix::fs::OFlags;
-use std::borrow::Cow;
 use std::ffi::OsStr;
 use std::path::{Component, Path, PathBuf};
 use std::{fs, io, mem};
diff --git a/tests/fs_additional.rs b/tests/fs_additional.rs
index 7a6c3397..1730a223 100644
--- a/tests/fs_additional.rs
+++ b/tests/fs_additional.rs
@@ -1426,111 +1426,15 @@ fn trailing_slash_symlink() {
     let sandbox = check!(tmpdir.open_dir("sandbox"));
 
     for path in ["hidden", "hidden/", "indirect", "indirect/"] {
-        error!(
-            sandbox.open_dir(path),
-            "a path led outside of the filesystem"
-        );
-        error!(
-            sandbox.read_dir(path),
-            "a path led outside of the filesystem"
-        );
-        error!(
-            sandbox.canonicalize(path),
-            "a path led outside of the filesystem"
-        );
-    }
-}
-
-/// Similar to `trailing_slash_symlink`, but populates the test directory
-/// outside the sandbox, so it can cover more cases.
-#[test]
-fn trailing_slash_symlink_more() {
-    let tmpdir = tempfile::tempdir().unwrap();
-
-    check!(std::fs::create_dir(tmpdir.path().join("sandbox")));
-    #[cfg(unix)]
-    {
-        check!(std::os::unix::fs::symlink(
-            "../outside",
-            tmpdir.path().join("sandbox/hidden")
-        ));
-        check!(std::os::unix::fs::symlink(
-            "hidden/",
-            tmpdir.path().join("sandbox/indirect")
-        ));
-        check!(std::os::unix::fs::symlink(
-            "/.",
-            tmpdir.path().join("sandbox/root_link")
-        ));
-    }
-    #[cfg(windows)]
-    {
-        check!(std::os::windows::fs::symlink_dir(
-            "../outside",
-            tmpdir.path().join("sandbox/hidden")
-        ));
-        check!(std::os::windows::fs::symlink_dir(
-            "hidden/",
-            tmpdir.path().join("sandbox/indirect")
-        ));
-        check!(std::os::windows::fs::symlink_dir(
-            "/.",
-            tmpdir.path().join("sandbox/root_link")
-        ));
-    }
-    #[cfg(not(any(unix, windows)))]
-    {
-        compile_error!("not implemented yet");
-    }
-
-    let tmpdir = check!(Dir::open_ambient_dir(tmpdir.path(), ambient_authority()));
-
-    let sandbox = check!(tmpdir.open_dir("sandbox"));
-
-    for path in [
-        "hidden",
-        "hidden/",
-        "indirect",
-        "indirect/",
-        "root_link",
-        "root_link/",
-    ] {
-        error!(
-            sandbox.open_dir(path),
-            "a path led outside of the filesystem"
-        );
-        error!(
-            sandbox.read_dir(path),
-            "a path led outside of the filesystem"
-        );
-        error!(
-            sandbox.canonicalize(path),
-            "a path led outside of the filesystem"
-        );
-    }
-}
-
-/// Test interactions between symlinks and trailing slashes.
-#[test]
-fn trailing_slash_symlink() {
-    let tmpdir = tmpdir();
-
-    check!(tmpdir.create_dir("sandbox"));
-    check!(symlink_dir("../outside", &tmpdir, "sandbox/hidden"));
-    check!(symlink_dir("hidden/", &tmpdir, "sandbox/indirect"));
-
-    let sandbox = check!(tmpdir.open_dir("sandbox"));
-
-    for path in ["hidden", "hidden/", "indirect", "indirect/"] {
-        error!(
+        error_contains!(
             sandbox.open_dir(path),
             "a path led outside of the filesystem"
         );
-        error!(
+        error_contains!(
             sandbox.read_dir(path),
             "a path led outside of the filesystem"
         );
-        error!(
+        error_contains!(
             sandbox.canonicalize(path),
             "a path led outside of the filesystem"
         );
@@ -1591,15 +1495,15 @@ fn trailing_slash_symlink_more() {
         "root_link",
         "root_link/",
     ] {
-        error!(
+        error_contains!(
             sandbox.open_dir(path),
             "a path led outside of the filesystem"
         );
-        error!(
+        error_contains!(
             sandbox.read_dir(path),
             "a path led outside of the filesystem"
         );
-        error!(
+        error_contains!(
             sandbox.canonicalize(path),
             "a path led outside of the filesystem"
         );