diff --git a/content/browser/file_system_access/file_system_access_handle_base.cc b/content/browser/file_system_access/file_system_access_handle_base.cc
index 1e5e4ba10e3882..c9b892db061163 100644
--- a/content/browser/file_system_access/file_system_access_handle_base.cc
+++ b/content/browser/file_system_access/file_system_access_handle_base.cc
@@ -32,9 +32,13 @@
 #include "third_party/blink/public/mojom/file_system_access/file_system_access_error.mojom-forward.h"
 
 namespace features {
+// TODO(crbug.com/1381621): This feature was disabled since it does not match
+// standard POSIX behavior. We should explore adding a flag to allow opting in
+// to overwriting moves. See discussion at
+// https://github.com/whatwg/fs/pull/10#issuecomment-1322993643.
 BASE_FEATURE(kFileSystemAccessDoNotOverwriteOnMove,
              "FileSystemAccessDoNotOverwriteOnMove",
-             base::FEATURE_ENABLED_BY_DEFAULT);
+             base::FEATURE_DISABLED_BY_DEFAULT);
 }  // namespace features
 
 namespace content {
diff --git a/content/browser/file_system_access/file_system_access_handle_base.h b/content/browser/file_system_access/file_system_access_handle_base.h
index cee1cb4503dd33..7ff6d3c5689f76 100644
--- a/content/browser/file_system_access/file_system_access_handle_base.h
+++ b/content/browser/file_system_access/file_system_access_handle_base.h
@@ -19,7 +19,7 @@
 #include "third_party/blink/public/mojom/permissions/permission_status.mojom.h"
 
 namespace features {
-// TODO(crbug.com/1366652): Remove this flag eventually.
+// TODO(crbug.com/1381621): Remove this flag eventually.
 // When enabled, move() will result in a promise rejection when the specified
 // destination to move to exists.
 BASE_DECLARE_FEATURE(kFileSystemAccessDoNotOverwriteOnMove);
diff --git a/third_party/blink/web_tests/external/wpt/fs/FileSystemFileHandle-move.https.any-expected.txt b/third_party/blink/web_tests/external/wpt/fs/FileSystemFileHandle-move.https.any-expected.txt
new file mode 100644
index 00000000000000..891983b2b381cd
--- /dev/null
+++ b/third_party/blink/web_tests/external/wpt/fs/FileSystemFileHandle-move.https.any-expected.txt
@@ -0,0 +1,24 @@
+This is a testharness.js-based test.
+PASS move(name) to rename a file
+PASS get a handle to a moved file
+PASS move(name) to rename a file the same name
+PASS move("") to rename a file fails
+PASS move(name) can be called multiple times
+PASS move(name) with a name with a trailing period should fail
+PASS move(name) with a name with invalid characters should fail
+PASS move(name) while the file has an open writable fails
+FAIL move(name) while the destination file has an open writable fails assert_unreached: Should have rejected: undefined Reached unreachable code
+PASS move(dir, name) to rename a file
+PASS move(dir, name) to rename a file the same name
+PASS move(dir) to move a file to a new directory
+PASS move(dir, "") to move a file to a new directory fails
+PASS move(dir, name) to move a file to a new directory
+PASS move(dir) can be called multiple times
+PASS move(dir, name) can be called multiple times
+PASS move(dir, name) with a name with invalid characters should fail
+PASS move(dir) while the file has an open writable fails
+PASS move(dir, name) while the file has an open writable fails
+FAIL move(dir) while the destination file has an open writable fails assert_unreached: Should have rejected: undefined Reached unreachable code
+FAIL move(dir, name) while the destination file has an open writable fails assert_unreached: Should have rejected: undefined Reached unreachable code
+Harness: the test ran to completion.
+
diff --git a/third_party/blink/web_tests/external/wpt/fs/FileSystemFileHandle-move.https.any.worker-expected.txt b/third_party/blink/web_tests/external/wpt/fs/FileSystemFileHandle-move.https.any.worker-expected.txt
new file mode 100644
index 00000000000000..891983b2b381cd
--- /dev/null
+++ b/third_party/blink/web_tests/external/wpt/fs/FileSystemFileHandle-move.https.any.worker-expected.txt
@@ -0,0 +1,24 @@
+This is a testharness.js-based test.
+PASS move(name) to rename a file
+PASS get a handle to a moved file
+PASS move(name) to rename a file the same name
+PASS move("") to rename a file fails
+PASS move(name) can be called multiple times
+PASS move(name) with a name with a trailing period should fail
+PASS move(name) with a name with invalid characters should fail
+PASS move(name) while the file has an open writable fails
+FAIL move(name) while the destination file has an open writable fails assert_unreached: Should have rejected: undefined Reached unreachable code
+PASS move(dir, name) to rename a file
+PASS move(dir, name) to rename a file the same name
+PASS move(dir) to move a file to a new directory
+PASS move(dir, "") to move a file to a new directory fails
+PASS move(dir, name) to move a file to a new directory
+PASS move(dir) can be called multiple times
+PASS move(dir, name) can be called multiple times
+PASS move(dir, name) with a name with invalid characters should fail
+PASS move(dir) while the file has an open writable fails
+PASS move(dir, name) while the file has an open writable fails
+FAIL move(dir) while the destination file has an open writable fails assert_unreached: Should have rejected: undefined Reached unreachable code
+FAIL move(dir, name) while the destination file has an open writable fails assert_unreached: Should have rejected: undefined Reached unreachable code
+Harness: the test ran to completion.
+