Array.prototype.some spec-compliant polyfill
An ES2015 spec-compliant `Array.prototype.entries` shim/polyfill/replacement that works as far down as ES3.
An ES5 mostly-spec-compliant `Object.getPrototypeOf` sham/polyfill/replacement that works in as many engines as possible.
An ES-spec-compliant Number.isFinite shim/polyfill/replacement that works as far down as ES3
An ES2015 spec-compliant `Map` shim/polyfill/replacement that works as far down as ES3.
An ESnext spec-compliant `Set` shim/polyfill/replacement that works as far down as ES3.
ES spec-compliant Array.prototype.concat shim/polyfill/replacement that works as far down as ES3
An ES-spec-compliant shim/polyfill/replacement for the Annex B String.prototype HTML methods that works as far down as ES3
An ES-spec-compliant Math.log10 shim/polyfill/replacement that works as far down as ES3
An ES-spec-compliant Number.prototype.toExponential shim/polyfill/replacement that works as far down as ES3
An ES-spec-compliant (proposed) `String.prototype.at`shim/polyfill/replacement that works as far down as ES3.
An ESnext spec-compliant `String.prototype.isWellFormed` shim/polyfill/replacement that works as far down as ES3.
An ESnext spec-compliant `String.prototype.toWellFormed` shim/polyfill/replacement that works as far down as ES3.
ES spec-compliant `String.prototype.substr` shim/polyfill/replacement that works as far down as ES3
An ES spec-compliant `Array.prototype.push` shim/polyfill/replacement that works as far down as ES3.
ES spec-compliant `Array.prototype.join` shim/polyfill/replacement that works as far down as ES3
ES spec-compliant Array.prototype.unshift shim/polyfill/replacement that works as far down as ES3
ES spec-compliant Array.prototype.splice shim/polyfill/replacement that works as far down as ES3
An ES-spec-compliant `String.prototype.lastIndexOf`shim/polyfill/replacement that works as far down as ES3.