NativeScript ES2016+ compatibility table

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NativeScript V8 JavaScriptCore
⬤ Minor difference (1 point) ⬤ Small feature (2 points) ⬤ Medium feature (4 points) ⬤ Large feature (8 points)

		NativeScript						Desktop browsers
Feature name►	Current browser^97%	NS 6.5 Android v8^81%	NS 7.0 Android v8^81%	NS 8.0 Android v8^81%	NS 6.5 iOS JSC^68%	NS 7.0 iOS v8^87%	NS 8.0 iOS v8^94%	CH 89^99%	CH 90^99%	SF 14 Beta^91%	SF TP^93%
2016 features
§exponentiation (**) operator ►	3/3	3/3	3/3	3/3	3/3	3/3	3/3	3/3	3/3	3/3	3/3
§basic supportc	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§assignmentc	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§early syntax error for unary negation without parensc	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§Array.prototype.includes ►	3/3	3/3	3/3	3/3	3/3	3/3	3/3	3/3	3/3	3/3	3/3
§Array.prototype.includes c	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§Array.prototype.includes is genericc	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§%TypedArray%.prototype.includes c	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
2016 misc
§generator functions can't be used with "new" ^[1]c	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§generator throw() caught by inner generator ^[2]c	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§strict fn w/ non-strict non-simple params is error ^[3]c	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§nested rest destructuring, declarations ^[4]c	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§nested rest destructuring, parameters ^[5]c	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§Proxy, "enumerate" handler removed ^[6]c	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§Proxy internal calls, Array.prototype.includesc	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
2017 features
§Object static methods►	4/4	4/4	4/4	4/4	4/4	4/4	4/4	4/4	4/4	4/4	4/4
§Object.values c	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§Object.entries c	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§Object.getOwnPropertyDescriptors c	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§Object.getOwnPropertyDescriptors doesn't provide undefined descriptorsc	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§String padding►	2/2	2/2	2/2	2/2	2/2	2/2	2/2	2/2	2/2	2/2	2/2
§String.prototype.padStart c	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§String.prototype.padEnd c	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§trailing commas in function syntax ►	2/2	2/2	2/2	2/2	2/2	2/2	2/2	2/2	2/2	2/2	2/2
§in parameter lists c	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§in argument lists c	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§async functions ►	14/16	16/16	16/16	16/16	16/16	16/16	16/16	16/16	16/16	16/16	16/16
§returnc	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§throwc	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§no line break between async and functionc	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§no "prototype" propertyc	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§await c	No	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§await, rejectionc	No	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§must await a valuec	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§can await non-Promise valuesc	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§cannot await in parametersc	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§async methods, object literalsc	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§async methods, classesc	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§async arrow functions in methods, classesc	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§async arrow functionsc	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§correct prototype chainc	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§async function prototype, Symbol.toStringTagc	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§async function constructorc	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§shared memory and atomics►	11/17	17/17	17/17	17/17	0/17	17/17	16/17	17/17	17/17	0/17	0/17
§SharedArrayBuffer c	No	Yes	Yes	Yes	No	Yes	Yes	Yes	Yes	No^[7]	No^[7]
§SharedArrayBuffer[Symbol.species]c	No	Yes	Yes	Yes	No	Yes	Yes	Yes	Yes	No^[7]	No^[7]
§SharedArrayBuffer.prototype.byteLength c	No	Yes	Yes	Yes	No	Yes	Yes	Yes	Yes	No^[7]	No^[7]
§SharedArrayBuffer.prototype.slice c	No	Yes	Yes	Yes	No	Yes	Yes	Yes	Yes	No^[7]	No^[7]
§SharedArrayBuffer.prototype[Symbol.toStringTag]c	No	Yes	Yes	Yes	No	Yes	Yes	Yes	Yes	No^[7]	No^[7]
§Atomics.add c	Yes	Yes	Yes	Yes	No	Yes	Yes	Yes	Yes	No^[7]	No^[7]
§Atomics.and c	Yes	Yes	Yes	Yes	No	Yes	Yes	Yes	Yes	No^[7]	No^[7]
§Atomics.compareExchange c	Yes	Yes	Yes	Yes	No	Yes	Yes	Yes	Yes	No^[7]	No^[7]
§Atomics.exchange c	Yes	Yes	Yes	Yes	No	Yes	Yes	Yes	Yes	No^[7]	No^[7]
§Atomics.wait c	Yes	Yes	Yes	Yes	No	Yes	Yes	Yes	Yes	No^[7]	No^[7]
§Atomics.wake c	No	Yes	Yes	Yes	No	Yes	No	Yes	Yes	No^[7]	No^[7]
§Atomics.isLockFree c	Yes	Yes	Yes	Yes	No	Yes	Yes	Yes	Yes	No^[7]	No^[7]
§Atomics.load c	Yes	Yes	Yes	Yes	No	Yes	Yes	Yes	Yes	No^[7]	No^[7]
§Atomics.or c	Yes	Yes	Yes	Yes	No	Yes	Yes	Yes	Yes	No^[7]	No^[7]
§Atomics.store c	Yes	Yes	Yes	Yes	No	Yes	Yes	Yes	Yes	No^[7]	No^[7]
§Atomics.sub c	Yes	Yes	Yes	Yes	No	Yes	Yes	Yes	Yes	No^[7]	No^[7]
§Atomics.xor c	Yes	Yes	Yes	Yes	No	Yes	Yes	Yes	Yes	No^[7]	No^[7]
2017 misc
§RegExp "u" flag, case foldingc	Yes	No	No	No	Yes	No	No	Yes	Yes	Yes	Yes
§arguments.caller removed c	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
2017 annex b
§Object.prototype getter/setter methods►	16/16	16/16	16/16	16/16	16/16	16/16	16/16	16/16	16/16	16/16	16/16
§__defineGetter__ c	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§__defineGetter__, symbolsc	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§__defineGetter__, ToObject(this)c	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§__defineSetter__ c	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§__defineSetter__, symbolsc	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§__defineSetter__, ToObject(this)c	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§__lookupGetter__ c	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§__lookupGetter__, prototype chainc	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§__lookupGetter__, symbolsc	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§__lookupGetter__, ToObject(this)c	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§__lookupGetter__, data properties can shadow accessorsc	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§__lookupSetter__ c	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§__lookupSetter__, prototype chainc	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§__lookupSetter__, symbolsc	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§__lookupSetter__, ToObject(this)c	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§__lookupSetter__, data properties can shadow accessorsc	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§Proxy internal calls, getter/setter methods►	4/4	4/4	4/4	4/4	4/4	4/4	4/4	4/4	4/4	4/4	4/4
§__defineGetter__c	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§__defineSetter__c	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§__lookupGetter__c	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§__lookupSetter__c	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§assignments allowed in for-in head in non-strict mode c	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
2018 features
§object rest/spread properties►	2/2	2/2	2/2	2/2	2/2	2/2	2/2	2/2	2/2	2/2	2/2
§object rest propertiesc	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§object spread propertiesc	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§Promise.prototype.finally ►	3/3	3/3	3/3	3/3	3/3	2/3	3/3	3/3	3/3	3/3	3/3
§basic supportc	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§don't change resolution valuec	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§change rejection valuec	Yes	Yes	Yes	Yes	Yes	No	Yes	Yes	Yes	Yes	Yes
§s (dotAll) flag for regular expressions c	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§RegExp named capture groups c	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§RegExp Lookbehind Assertions c	Yes	Yes	Yes	Yes	No	Yes	Yes	Yes	Yes	No	No
§RegExp Unicode Property Escapes c	Yes	No	No	No	Yes	No	No	Yes	Yes	Yes	Yes
§Asynchronous Iterators►	2/2	2/2	2/2	2/2	2/2	2/2	2/2	2/2	2/2	2/2	2/2
§async generatorsc	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§for-await-of loops c	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
2018 misc
§Proxy "ownKeys" handler, duplicate keys for non-extensible targets c	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§template literal revisionc	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
2019 features
§Object.fromEntries c	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§string trimming►	4/4	4/4	4/4	4/4	4/4	4/4	4/4	4/4	4/4	4/4	4/4
§String.prototype.trimLeft c	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§String.prototype.trimRight c	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§String.prototype.trimStart c	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§String.prototype.trimEnd c	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§Array.prototype.{flat, flatMap}^[8]►	3/3	3/3	3/3	3/3	3/3	3/3	3/3	3/3	3/3	3/3	3/3
§Array.prototype.flat c	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§Array.prototype.flatMap c	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§flat and flatMap in Array.prototype[@@unscopables]c	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
2019 misc
§optional catch binding►	3/3	3/3	3/3	3/3	3/3	3/3	3/3	3/3	3/3	3/3	3/3
§basicc	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§awaitc	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§yieldc	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§Symbol.prototype.description ►	3/3	3/3	3/3	3/3	3/3	3/3	3/3	3/3	3/3	3/3	3/3
§basicc	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§empty descriptionc	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§undefined descriptionc	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§Function.prototype.toString revision ►	7/7	7/7	7/7	7/7	4/7	7/7	7/7	7/7	7/7	4/7	4/7
§functions created with the Function constructorc	Yes	Yes	Yes	Yes	No	Yes	Yes	Yes	Yes	?	?
§arrowsc	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§[native code]c	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§class expression with implicit constructorc	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§class expression with explicit constructorc	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§unicode escape sequences in identifiersc	Yes	Yes	Yes	Yes	No	Yes	Yes	Yes	Yes	?	?
§methods and computed property namesc	Yes	Yes	Yes	Yes	No	Yes	Yes	Yes	Yes	?	?
§JSON superset►	2/2	2/2	2/2	2/2	2/2	2/2	2/2	2/2	2/2	2/2	2/2
§LINE SEPARATOR can appear in string literalsc	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§PARAGRAPH SEPARATOR can appear in string literalsc	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§Well-formed JSON.stringify c	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
2020 features
§String.prototype.matchAll ►	2/2	2/2	2/2	2/2	1/2	2/2	2/2	2/2	2/2	2/2	2/2
§basic functionalityc	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§throws on non-global regexc	Yes	Yes	Yes	Yes	No	Yes	Yes	Yes	Yes	Yes	Yes
§BigInt ►	8/8	8/8	8/8	8/8	0/8	8/8	8/8	8/8	8/8	4/8	8/8
§basic functionalityc	Yes	Yes	Yes	Yes	No	Yes	Yes	Yes	Yes	Yes	Yes
§constructorc	Yes	Yes	Yes	Yes	No	Yes	Yes	Yes	Yes	Yes	Yes
§BigInt.asUintNc	Yes	Yes	Yes	Yes	No	Yes	Yes	Yes	Yes	Yes	Yes
§BigInt.asIntNc	Yes	Yes	Yes	Yes	No	Yes	Yes	Yes	Yes	Yes	Yes
§BigInt64Arrayc	Yes	Yes	Yes	Yes	No	Yes	Yes	Yes	Yes	?	Yes
§BigUint64Arrayc	Yes	Yes	Yes	Yes	No	Yes	Yes	Yes	Yes	?	Yes
§DataView.prototype.getBigInt64c	Yes	Yes	Yes	Yes	No	Yes	Yes	Yes	Yes	?	Yes
§DataView.prototype.getBigUint64c	Yes	Yes	Yes	Yes	No	Yes	Yes	Yes	Yes	?	Yes
§Promise.allSettled c	Yes	?	?	?	?	?	?	Yes	Yes	Yes	Yes
§globalThis ►	2/2	2/2	2/2	2/2	2/2	2/2	2/2	2/2	2/2	2/2	2/2
§"globalThis" global property is global objectc	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§"globalThis" global property has correct property descriptorc	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
§optional chaining operator (?.) ►	5/5	4/5	4/5	4/5	0/5	4/5	4/5	4/5	4/5	5/5	5/5
§optional property accessc	Yes	Yes	Yes	Yes	No	Yes	Yes	Yes	Yes	Yes	Yes
§optional bracket accessc	Yes	Yes	Yes	Yes	No	Yes	Yes	Yes	Yes	Yes	Yes
§optional method callc	Yes	Yes	Yes	Yes	No	Yes	Yes	Yes	Yes	Yes	Yes
§optional function callc	Yes	Yes	Yes	Yes	No	Yes	Yes	Yes	Yes	Yes	Yes
§spread parameters after optional chainingc	Yes	No	No	No	No	No	No	No	No	Yes	Yes
§nullish coalescing operator (??) c	Yes	Yes	Yes	Yes	No	Yes	Yes	Yes	Yes	Yes	Yes
2021 features
§String.prototype.replaceAll c	Yes	No	No	No	No	No	Yes	Yes	Yes	Yes	Yes
§Promise.any ►	2/2	0/2	0/2	0/2	0/2	0/2	2/2	2/2	2/2	2/2	2/2
§fulfillmentc	Yes	No	No	No	No	No	Yes	Yes	Yes	Yes	Yes
§AggregateErrorc	Yes	No	No	No	No	No	Yes	Yes	Yes	Yes	Yes
§WeakReferences►	2/2	0/2	0/2	0/2	0/2	2/2	2/2	2/2	2/2	2/2	2/2
§WeakRef minimal supportc	Yes	No	No	No	No	Yes	Yes	Yes	Yes	Yes	Yes
§FinalizationRegistry minimal supportc	Yes	No	No	No	No	Yes	Yes	Yes	Yes	Yes	Yes
§Logical Assignment►	9/9	0/9	0/9	0/9	0/9	0/9	9/9	9/9	9/9	9/9	9/9
§\|\|= basic supportc	Yes	No	No	No	No	No	Yes	Yes	Yes	Yes	Yes
§\|\|= short-circuiting behaviourc	Yes	No	No	No	No	No	Yes	Yes	Yes	Yes	Yes
§\|\|= setter not unecessarily invokedc	Yes	No	No	No	No	No	Yes	Yes	Yes	Yes	Yes
§&&= basic supportc	Yes	No	No	No	No	No	Yes	Yes	Yes	Yes	Yes
§&&= short-circuiting behaviourc	Yes	No	No	No	No	No	Yes	Yes	Yes	Yes	Yes
§&&= setter not unecessarily invokedc	Yes	No	No	No	No	No	Yes	Yes	Yes	Yes	Yes
§??= basic supportc	Yes	No	No	No	No	No	Yes	Yes	Yes	Yes	Yes
§??= short-circuiting behaviourc	Yes	No	No	No	No	No	Yes	Yes	Yes	Yes	Yes
§??= setter not unecessarily invokedc	Yes	No	No	No	No	No	Yes	Yes	Yes	Yes	Yes
§numeric separatorsc	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes

Thanks to Kangax, webspacedspace, zloirock and the rest of the people who contributed to Kangax ES Compatibility Table

This site uses the base of the awesome compat-table and adds all the code to handle the additional testing on the NativeScript runtimes, and ability to export the data and collate it back to these tables...

^[1] TC39 meeting notes from July 28, 2015.

^[2] 'Semantics of yield* in throw case' GitHub issue in ECMA-262 repo.

^[3] TC39 meeting notes from July 29, 2015.

^[4] TC39 meeting notes from July 28, 2015.

^[5] TC39 meeting notes from July 28, 2015.

^[6] 'Normative: Remove [[Enumerate]] and associated reflective capabilities' GitHub Pull Request in ECMA-262 repo.

^[7] The feature was temporarily disabled to mitigate the Meltdown and Spectre CPU bugs.

^[8] Name of Array.prototype.flatten() changed to Array.prototype.flat() due to web compatibility issues.