diff --git a/js/src/frontend/Parser.cpp b/js/src/frontend/Parser.cpp
index 7f8230bf55df..e9e3b969983c 100644
--- a/js/src/frontend/Parser.cpp
+++ b/js/src/frontend/Parser.cpp
@@ -7070,7 +7070,7 @@ GeneralParser<ParseHandler, Unit>::classDefinition(
     }
 
     if (numFieldKeys > 0) {
-      if (!noteDeclaredName(cx_->names().dotFieldKeys, DeclarationKind::Var,
+      if (!noteDeclaredName(cx_->names().dotFieldKeys, DeclarationKind::Let,
                             namePos)) {
         return null();
       }
diff --git a/js/src/jit-test/tests/fields/bug1540798.js b/js/src/jit-test/tests/fields/bug1540798.js
index 03b904022bad..970cf1b9867d 100644
--- a/js/src/jit-test/tests/fields/bug1540798.js
+++ b/js/src/jit-test/tests/fields/bug1540798.js
@@ -1,3 +1,5 @@
+// |jit-test| --enable-experimental-fields
+
 try { evaluate(`
 class constructor  { get;                                           } // Long line is long
 // Long line XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
diff --git a/js/src/jit-test/tests/fields/bug1547133.js b/js/src/jit-test/tests/fields/bug1547133.js
new file mode 100644
index 000000000000..a3c5df85aa0d
--- /dev/null
+++ b/js/src/jit-test/tests/fields/bug1547133.js
@@ -0,0 +1,5 @@
+// |jit-test| --enable-experimental-fields
+
+class C47 {
+  static method(s = class { [y75] = 42; }) {}
+}
diff --git a/js/src/jit-test/tests/fields/bug1547136.js b/js/src/jit-test/tests/fields/bug1547136.js
new file mode 100644
index 000000000000..5db540daceb5
--- /dev/null
+++ b/js/src/jit-test/tests/fields/bug1547136.js
@@ -0,0 +1,3 @@
+// |jit-test| --enable-experimental-fields
+
+try {} catch ([ c = class { ["s"] }]) {}