--- a/js/src/builtin/Intl.cpp
+++ b/js/src/builtin/Intl.cpp
@@ -1669,16 +1669,17 @@ dateTimeFormat_toSource(JSContext* cx, u
 
 static const JSFunctionSpec dateTimeFormat_static_methods[] = {
     JS_SELF_HOSTED_FN("supportedLocalesOf", "Intl_DateTimeFormat_supportedLocalesOf", 1, 0),
     JS_FS_END
 };
 
 static const JSFunctionSpec dateTimeFormat_methods[] = {
     JS_SELF_HOSTED_FN("resolvedOptions", "Intl_DateTimeFormat_resolvedOptions", 0, 0),
+    JS_SELF_HOSTED_FN("formatToParts", "Intl_DateTimeFormat_formatToParts", 0, 0),
 #if JS_HAS_TOSOURCE
     JS_FN(js_toSource_str, dateTimeFormat_toSource, 0, 0),
 #endif
     JS_FS_END
 };
 
 /**
  * DateTimeFormat constructor.
@@ -1806,33 +1807,16 @@ CreateDateTimeFormatPrototype(JSContext*
     }
     if (!DefineProperty(cx, proto, cx->names().format, UndefinedHandleValue,
                         JS_DATA_TO_FUNC_PTR(JSGetterOp, &getter.toObject()),
                         nullptr, JSPROP_GETTER | JSPROP_SHARED))
     {
         return nullptr;
     }
 
-    // If the still-experimental DateTimeFormat.prototype.formatToParts method
-    // is enabled, also add it.
-    if (cx->compartment()->creationOptions().experimentalDateTimeFormatFormatToPartsEnabled()) {
-        RootedValue ftp(cx);
-        HandlePropertyName name = cx->names().formatToParts;
-        if (!GlobalObject::getSelfHostedFunction(cx, cx->global(),
-                    cx->names().DateTimeFormatFormatToParts,
-                    name,
-                    0, &ftp))
-        {
-            return nullptr;
-        }
-
-        if (!DefineProperty(cx, proto, cx->names().formatToParts, ftp, nullptr, nullptr, 0))
-            return nullptr;
-    }
-
     RootedValue options(cx);
     if (!CreateDefaultOptions(cx, &options))
         return nullptr;
 
     // 12.2.1 and 12.3
     if (!IntlInitialize(cx, proto, cx->names().InitializeDateTimeFormat, UndefinedHandleValue,
                         options))
     {

--- a/js/src/jsapi.h
+++ b/js/src/jsapi.h
@@ -2140,17 +2140,16 @@ class JS_PUBLIC_API(CompartmentCreationO
   public:
     CompartmentCreationOptions()
       : addonId_(nullptr),
         traceGlobal_(nullptr),
         invisibleToDebugger_(false),
         mergeable_(false),
         preserveJitCode_(false),
         cloneSingletons_(false),
-        experimentalDateTimeFormatFormatToPartsEnabled_(false),
         sharedMemoryAndAtomics_(false),
         secureContext_(false)
     {
         zone_.spec = JS::FreshZone;
     }
 
     // A null add-on ID means that the compartment is not associated with an
     // add-on.
@@ -2205,33 +2204,16 @@ class JS_PUBLIC_API(CompartmentCreationO
     }
 
     bool cloneSingletons() const { return cloneSingletons_; }
     CompartmentCreationOptions& setCloneSingletons(bool flag) {
         cloneSingletons_ = flag;
         return *this;
     }
 
-    // ECMA-402 is considering adding a "formatToParts" DateTimeFormat method,
-    // that exposes not just a formatted string but its ordered subcomponents.
-    // The method, its semantics, and its name are all well short of being
-    // finalized, so for now it's exposed *only* if requested.
-    //
-    // Until "formatToParts" is included in a final specification edition, it's
-    // subject to change or removal at any time.  Do *not* rely on it in
-    // mission-critical code that can't be changed if ECMA-402 decides not to
-    // accept the method in its current form.
-    bool experimentalDateTimeFormatFormatToPartsEnabled() const {
-        return experimentalDateTimeFormatFormatToPartsEnabled_;
-    }
-    CompartmentCreationOptions& setExperimentalDateTimeFormatFormatToPartsEnabled(bool flag) {
-        experimentalDateTimeFormatFormatToPartsEnabled_ = flag;
-        return *this;
-    }
-
     bool getSharedMemoryAndAtomicsEnabled() const;
     CompartmentCreationOptions& setSharedMemoryAndAtomicsEnabled(bool flag);
 
     // This flag doesn't affect JS engine behavior.  It is used by Gecko to
     // mark whether content windows and workers are "Secure Context"s. See
     // https://w3c.github.io/webappsec-secure-contexts/
     // https://bugzilla.mozilla.org/show_bug.cgi?id=1162772#c34
     bool secureContext() const { return secureContext_; }
@@ -2246,17 +2228,16 @@ class JS_PUBLIC_API(CompartmentCreationO
     union {
         ZoneSpecifier spec;
         void* pointer; // js::Zone* is not exposed in the API.
     } zone_;
     bool invisibleToDebugger_;
     bool mergeable_;
     bool preserveJitCode_;
     bool cloneSingletons_;
-    bool experimentalDateTimeFormatFormatToPartsEnabled_;
     bool sharedMemoryAndAtomics_;
     bool secureContext_;
 };
 
 /**
  * CompartmentBehaviors specifies behaviors of a compartment that can be
  * changed after the compartment's been created.
  */

--- a/js/src/shell/js.cpp
+++ b/js/src/shell/js.cpp
@@ -4447,21 +4447,16 @@ NewGlobal(JSContext* cx, unsigned argc, 
         if (v.isBoolean())
             creationOptions.setInvisibleToDebugger(v.toBoolean());
 
         if (!JS_GetProperty(cx, opts, "cloneSingletons", &v))
             return false;
         if (v.isBoolean())
             creationOptions.setCloneSingletons(v.toBoolean());
 
-        if (!JS_GetProperty(cx, opts, "experimentalDateTimeFormatFormatToPartsEnabled", &v))
-            return false;
-        if (v.isBoolean())
-            creationOptions.setExperimentalDateTimeFormatFormatToPartsEnabled(v.toBoolean());
-
         if (!JS_GetProperty(cx, opts, "sameZoneAs", &v))
             return false;
         if (v.isObject())
             creationOptions.setSameZoneAs(UncheckedUnwrap(&v.toObject()));
 
         if (!JS_GetProperty(cx, opts, "disableLazyParsing", &v))
             return false;
         if (v.isBoolean())

--- a/js/src/tests/Intl/DateTimeFormat/formatToParts.js
+++ b/js/src/tests/Intl/DateTimeFormat/formatToParts.js
@@ -1,9 +1,9 @@
-// |reftest| skip-if(!this.hasOwnProperty("Intl")||!this.newGlobal||!newGlobal({experimentalDateTimeFormatFormatToPartsEnabled:true}).Intl.DateTimeFormat().formatToParts)
+// |reftest| skip-if(!this.hasOwnProperty("Intl"))
 // Any copyright is dedicated to the Public Domain.
 // http://creativecommons.org/licenses/publicdomain/
 
 // Tests the format function with a diverse set of locales and options.
 // Always use UTC to avoid dependencies on test environment.
 
 /*
  * Return true if A is equal to B, where equality on arrays and objects
@@ -42,65 +42,59 @@ function deepEqual(a, b) {
 function composeDate(parts) {
   return parts.map(({value}) => value)
               .reduce((string, part) => string + part);
 }
 
 var format;
 var date = Date.UTC(2012, 11, 17, 3, 0, 42);
 
-// The experimental formatToParts method is only exposed if specifically
-// requested.  Perform all tests using DateTimeFormat instances from a global
-// object with this method enabled.
-var DateTimeFormat =
-  newGlobal({experimentalDateTimeFormatFormatToPartsEnabled:true}).Intl.DateTimeFormat;
-
 // Locale en-US; default options.
-format = new DateTimeFormat("en-us", {timeZone: "UTC"});
+format = new Intl.DateTimeFormat("en-us", {timeZone: "UTC"});
 assertEq(deepEqual(format.formatToParts(date), [
   { type: 'month', value: '12' },
   { type: 'literal', value: '/' },
   { type: 'day', value: '17' },
   { type: 'literal', value: '/' },
   { type: 'year', value: '2012' }
 ]), true);
 
 // Just date
-format = new DateTimeFormat("en-us", {
+format = new Intl.DateTimeFormat("en-us", {
   year: 'numeric',
   month: 'numeric',
   day: 'numeric',
   timeZone: "UTC"});
 assertEq(deepEqual(format.formatToParts(date), [
   { type: 'month', value: '12' },
   { type: 'literal', value: '/' },
   { type: 'day', value: '17' },
   { type: 'literal', value: '/' },
   { type: 'year', value: '2012' }
 ]), true);
 assertEq(composeDate(format.formatToParts(date)), format.format(date));
 
 // Just time in hour24
-format = new DateTimeFormat("en-us", {
+format = new Intl.DateTimeFormat("en-us", {
   hour: 'numeric',
   minute: 'numeric',
   second: 'numeric',
   hour12: false,
   timeZone: "UTC"});
 assertEq(deepEqual(format.formatToParts(date), [
   { type: 'hour', value: '03' },
   { type: 'literal', value: ':' },
   { type: 'minute', value: '00' },
   { type: 'literal', value: ':' },
   { type: 'second', value: '42' }
 ]), true);
 assertEq(composeDate(format.formatToParts(date)), format.format(date));
 
 // Just time in hour12
-format = new DateTimeFormat("en-us", {
+format = new Intl.DateTimeFormat("en-us", {
   hour: 'numeric',
   minute: 'numeric',
   second: 'numeric',
   hour12: true,
   timeZone: "UTC"});
 assertEq(deepEqual(format.formatToParts(date), [
   { type: 'hour', value: '3' },
   { type: 'literal', value: ':' },
@@ -108,47 +102,47 @@ assertEq(deepEqual(format.formatToParts(
   { type: 'literal', value: ':' },
   { type: 'second', value: '42' },
   { type: 'literal', value: ' ' },
   { type: 'dayPeriod', value: 'AM' }
 ]), true);
 assertEq(composeDate(format.formatToParts(date)), format.format(date));
 
 // Just month.
-format = new DateTimeFormat("en-us", {
+format = new Intl.DateTimeFormat("en-us", {
   month: "narrow",
   timeZone: "UTC"});
 assertEq(deepEqual(format.formatToParts(date), [
   { type: 'month', value: 'D' }
 ]), true);
 assertEq(composeDate(format.formatToParts(date)), format.format(date));
 
 // Just weekday.
-format = new DateTimeFormat("en-us", {
+format = new Intl.DateTimeFormat("en-us", {
   weekday: "narrow",
   timeZone: "UTC"});
 assertEq(deepEqual(format.formatToParts(date), [
   { type: 'weekday', value: 'M' }
 ]), true);
 assertEq(composeDate(format.formatToParts(date)), format.format(date));
 
 // Year and era.
-format = new DateTimeFormat("en-us", {
+format = new Intl.DateTimeFormat("en-us", {
   year: "numeric",
   era: "short",
   timeZone: "UTC"});
 assertEq(deepEqual(format.formatToParts(date), [
   { type: 'year', value: '2012' },
   { type: 'literal', value: ' ' },
   { type: 'era', value: 'AD' }
 ]), true);
 assertEq(composeDate(format.formatToParts(date)), format.format(date));
 
 // Time and date
-format = new DateTimeFormat("en-us", {
+format = new Intl.DateTimeFormat("en-us", {
   weekday: 'long',
   year: 'numeric',
   month: 'numeric',
   day: 'numeric',
   hour: 'numeric',
   minute: 'numeric',
   second: 'numeric',
   hour12: true,

--- a/js/src/vm/CommonPropertyNames.h
+++ b/js/src/vm/CommonPropertyNames.h
@@ -111,17 +111,16 @@
     macro(flags, flags, "flags") \
     macro(float32, float32, "float32") \
     macro(Float32x4, Float32x4, "Float32x4") \
     macro(float64, float64, "float64") \
     macro(Float64x2, Float64x2, "Float64x2") \
     macro(forceInterpreter, forceInterpreter, "forceInterpreter") \
     macro(forEach, forEach, "forEach") \
     macro(format, format, "format") \
-    macro(formatToParts, formatToParts, "formatToParts") \
     macro(frame, frame, "frame") \
     macro(from, from, "from") \
     macro(futexOK, futexOK, "ok") \
     macro(futexNotEqual, futexNotEqual, "not-equal") \
     macro(futexTimedOut, futexTimedOut, "timed-out") \
     macro(gcCycleNumber, gcCycleNumber, "gcCycleNumber") \
     macro(Generator, Generator, "Generator") \
     macro(GeneratorFunction, GeneratorFunction, "GeneratorFunction") \

--- a/js/xpconnect/src/nsXPConnect.cpp
+++ b/js/xpconnect/src/nsXPConnect.cpp
@@ -432,22 +432,16 @@ InitGlobalObjectOptions(JS::CompartmentO
     bool shouldDiscardSystemSource = ShouldDiscardSystemSource();
     bool extraWarningsForSystemJS = ExtraWarningsForSystemJS();
 
     bool isSystem = nsContentUtils::IsSystemPrincipal(aPrincipal);
 
     if (isSystem) {
         // Make sure [SecureContext] APIs are visible:
         aOptions.creationOptions().setSecureContext(true);
-
-#if 0 // TODO: Reenable in Bug 1288653
-        // Enable the ECMA-402 experimental formatToParts in any chrome page
-        aOptions.creationOptions()
-                .setExperimentalDateTimeFormatFormatToPartsEnabled(true);
-#endif
     }
 
     if (shouldDiscardSystemSource) {
         bool discardSource = isSystem;
 
         aOptions.behaviors().setDiscardSource(discardSource);
     }