diff --git a/test262_config.toml b/test262_config.toml
index f3020ef1272..35c54989a2d 100644
--- a/test262_config.toml
+++ b/test262_config.toml
@@ -1,4 +1,4 @@
-commit = "dad2774b2eab2119cc8390ae65db4a5016de2dfe"
+commit = "8296db887368bbffa3379f995a1e628ddbe8421f"
 
 [ignored]
 # Not implemented yet:
@@ -35,6 +35,9 @@ features = [
     # https://tc39.es/proposal-defer-import-eval
     "import-defer",
 
+    # https://github.com/tc39/proposal-iterator-sequencing
+    "iterator-sequencing",
+
     # https://github.com/tc39/proposal-json-modules
     "json-modules",
 
@@ -75,4 +78,4 @@ features = [
     "caller",
 ]
 
-tests = []
+tests = ["sm"]
diff --git a/tests/tester/src/edition.rs b/tests/tester/src/edition.rs
index 38ca0896665..9fd774c8bf0 100644
--- a/tests/tester/src/edition.rs
+++ b/tests/tester/src/edition.rs
@@ -45,6 +45,10 @@ static FEATURE_EDITION: phf::Map<&'static str, SpecEdition> = phf::phf_map! {
     // https://github.com/tc39/proposal-import-assertions/
     "import-assertions"  => SpecEdition::ESNext,
 
+    // Iterator sequencing
+    // https://github.com/tc39/proposal-iterator-sequencing
+    "iterator-sequencing" => SpecEdition::ESNext,
+
     // JSON modules
     // https://github.com/tc39/proposal-json-modules
     "json-modules"  => SpecEdition::ESNext,
diff --git a/tests/tester/src/read.rs b/tests/tester/src/read.rs
index 1fac7223c2d..bbd437d799c 100644
--- a/tests/tester/src/read.rs
+++ b/tests/tester/src/read.rs
@@ -1,6 +1,7 @@
 //! Module to read the list of test suites from disk.
 
 use std::{
+    collections::HashMap,
     ffi::OsStr,
     fs,
     path::{Path, PathBuf},
@@ -10,7 +11,7 @@ use color_eyre::{
     eyre::{OptionExt, WrapErr},
     Result,
 };
-use rustc_hash::FxHashMap;
+use rustc_hash::{FxBuildHasher, FxHashMap};
 use serde::Deserialize;
 
 use crate::{HarnessFile, Ignored};
@@ -92,33 +93,10 @@ pub(super) enum TestFlag {
 
 /// Reads the Test262 defined bindings.
 pub(super) fn read_harness(test262_path: &Path) -> Result<Harness> {
-    fn read_harness_file(path: PathBuf) -> Result<HarnessFile> {
-        let content = fs::read_to_string(path.as_path())
-            .wrap_err_with(|| format!("error reading the harness file `{}`", path.display()))?;
-
-        Ok(HarnessFile {
-            content: content.into_boxed_str(),
-            path: path.into_boxed_path(),
-        })
-    }
-    let mut includes = FxHashMap::default();
-
-    for entry in fs::read_dir(test262_path.join("harness"))
-        .wrap_err("error reading the harness directory")?
-    {
-        let entry = entry?;
-        let file_name = entry.file_name();
-        let file_name = file_name.to_string_lossy();
+    let mut includes: HashMap<Box<str>, HarnessFile, FxBuildHasher> = FxHashMap::default();
 
-        if file_name == "assert.js" || file_name == "sta.js" || file_name == "doneprintHandle.js" {
-            continue;
-        }
+    read_harness_dir(&test262_path.join("harness"), &mut includes)?;
 
-        includes.insert(
-            file_name.into_owned().into_boxed_str(),
-            read_harness_file(entry.path())?,
-        );
-    }
     let assert = read_harness_file(test262_path.join("harness/assert.js"))?;
     let sta = read_harness_file(test262_path.join("harness/sta.js"))?;
     let doneprint_handle = read_harness_file(test262_path.join("harness/doneprintHandle.js"))?;
@@ -131,6 +109,40 @@ pub(super) fn read_harness(test262_path: &Path) -> Result<Harness> {
     })
 }
 
+fn read_harness_dir(
+    directory_name: &Path,
+    includes: &mut HashMap<Box<str>, HarnessFile, FxBuildHasher>,
+) -> Result<()> {
+    for entry in fs::read_dir(directory_name).wrap_err("error reading the harness directory")? {
+        let entry = entry?;
+        let file_name = entry.file_name();
+        let file_name = file_name.to_string_lossy().into_owned();
+
+        if directory_name.join(file_name.clone()).is_dir() {
+            read_harness_dir(&directory_name.join(file_name), includes)?;
+            continue;
+        }
+
+        if file_name == "assert.js" || file_name == "sta.js" || file_name == "doneprintHandle.js" {
+            continue;
+        }
+
+        includes.insert(file_name.into_boxed_str(), read_harness_file(entry.path())?);
+    }
+
+    Ok(())
+}
+
+fn read_harness_file(path: PathBuf) -> Result<HarnessFile> {
+    let content = fs::read_to_string(path.as_path())
+        .wrap_err_with(|| format!("error reading the harness file `{}`", path.display()))?;
+
+    Ok(HarnessFile {
+        content: content.into_boxed_str(),
+        path: path.into_boxed_path(),
+    })
+}
+
 /// Reads a test suite in the given path.
 pub(super) fn read_suite(
     path: &Path,