Changelog

v4.1.4

Fixed a crash when inlining a function into somewhere else when it has interdependent, non-removable variables.

Internal functions were replaced by Object.assign, Array.prototype.some, Array.prototype.find and Array.prototype.every.
A serious issue where some ESM-native code was broken was fixed.
Performance improvements were made.
Support for BigInt was added.
Inline efficiency was improved. Functions are now being inlined more proactively instead of being inlined only after another Compressor pass.

(Hotfix release. Reverts unmapped segments PR #342, which will be put back on Terser when the upstream issue is resolved)

Collisions between the arguments of inlined functions and names in the outer scope are now being avoided while inlining
Unmapped segments are now preserved when compressing a file which has source maps
Default values of functions are now correctly converted from Mozilla AST to Terser AST
JSON ⊂ ECMAScript spec (if you don't know what this is you don't need to)
Export AST_* classes to library users
Fixed issue with collapse_vars when functions are created with the same name as a variable which already exists
Added MutationObserverInit (Object with options for initialising a mutation observer) properties to the DOM property list
Custom Error subclasses are now internally used instead of old-school Error inheritance hacks.
Documentation fixes
Performance optimizations

breaking change: The variables property of all scopes has become a standard JavaScript Map as opposed to the old bespoke Dictionary object.
Typescript definitions were fixed
terser --help was fixed
The public interface was cleaned up
Fixed optimisation of Array and new Array
Added the keep_quoted=strict mode to mangle_props, which behaves more like Google Closure Compiler by mangling all unquoted property names, instead of reserving quoted property names automatically.
Fixed parent functions' parameters being shadowed in some cases
Allowed Terser to run in a situation where there are custom functions attached to Object.prototype
And more bug fixes, optimisations and internal changes

More DOM properties added to --mangle-properties's DOM property list
Closed issue where if 2 functions had the same argument name, Terser would not inline them together properly
Fixed issue with hasOwnProperty.call
You can now list files to minify in a Terser config file
Started replacing new Array(<number>) with an array literal
Started using ES6 capabilities like Set and the includes method for strings and arrays

Fixed issue where Terser being imported with import would cause it not to work due to the __esModule property. (PR #254 was submitted, which was nice, but since it wasn't a pure commonJS approach I decided to go with my own solution)

No longer leaves names like Array or Object or window as a SimpleStatement (statement which is just a single expression).
Add support for sections sourcemaps (IndexedSourceMapConsumer)
Drops node.js v4 and starts using commonJS
Is now built with rollup

Inlined spread syntax ([...[1, 2, 3], 4, 5] => [1, 2, 3, 4, 5]) in arrays and objects.
Fixed typo in compressor warning
Fixed inline source map input bug
Fixed parsing of template literals with unnecessary escapes (Like \\a)