WPT details: Present in test262. https://github.com/tc39/test262/tree/main/test/built-ins/Array/prototype/findLast https://github.com/tc39/test262/tree/main/test/built-ins/Array/prototype/findLastIndex https://github.com/tc39/test262/tree/main/test/built-ins/TypedArray/prototype/findLast https://github.com/tc39/test262/tree/main/test/built-ins/TypedArray/prototype/findLastIndex
This is a Stage 3 TC39 proposal that adds the methods findLast and findLastIndex to Array.prototype and the various TypedArray.prototypes. These methods are the "from the end" versions of find and findIndex.
Finding an element in an Array is a common operation. However, finding an element from the end of an Array is unergonomic. The current ergonomic solutions like `array.reverse().find` require unnecessary mutation or copying. This proposal adds "from the end" versions of the common `find` and `findIndex` methods: `findLast` and `findLastIndex`.
Explainers: https://github.com/tc39/proposal-array-find-from-last