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Version 1.71.1

- New JavaScript features! This version of GJS is based on SpiderMonkey
  91, an upgrade from the previous ESR (Extended Support Release) of
  SpiderMonkey 78.
  Here are the highlights of the new JavaScript features.
  For more information, look them up on MDN or

  * New syntax
    + Private class fields and methods are now supported. They start
      with `#` and are not accessible outside the class in which they are
    + The `??=` logical nullish assignment operator, which assigns the
      right-hand side value to the left-hand side variable if the
      variable is null or undefined.
    + The `&&=` logical-and assignment operator, which assigns the
      right-hand side value to the left-hand side variable if the variable is
    + The `||=` logical-or assignment operator, which assigns the
      right-hand side value to the left-hand side variable if the variable is
    + `export * as ... from ...` can be used to aggregate modules.
    + Regular expressions add the `d` flag, which if defined causes the
      resulting match object to have an `indices` property giving the
      positions in the string where capturing and named groups matched.
    + `static { ... }` blocks in classes allow initialization of classes
      at the time of creation of the class.

  * New APIs
    + Arrays, strings, and typed arrays have gained the `at()` method,
      which does the same thing as indexing with square brackets but also
      allows negative numbers, which count from the end, as in Python.
    + `Promise.any()`, which is similar to `Promise.race()` but resolves
      on the first successful sub-promise, instead of the first to resolve.
    + `Error()` now takes an options object as its second parameter,
      which may contain a `cause` property. This option is used to indicate when
      an error is caused by another error, but the first error is caught during
      error handling.
    + `WeakRef`, which allows you to hold a reference to an object while
      still allowing it to be garbage collected.
    + `dateStyle`, `timeStyle`, `fractionalSecondDigits`, and
      `dayPeriod` are now accepted as options in `Intl.DateTimeFormat()` and
    + `collation` is now accepted as an option in `Intl.Collator()`.
    + `Intl.DisplayNames` has been added, which allows you to get
      translations of language, region, currency, and script names.
    + `Intl.DateTimeFormat` has gained the `formatRange()` and
      `formatRangeToParts()` methods.

  * New behaviour
    + More numbering systems are supported in `Intl.NumberFormat`.
    + Top-level await ( allows
      you to use `await` statements outside of an `async` function in an ES
    + There are a lot of minor behaviour changes as SpiderMonkey's JS
      implementation conforms ever closer to existing ECMAScript
      standards and adopts new ones. For complete information, read the Firefox
      developer release notes:

- It's now possible to pass BigInt values to GObject-introspected
  functions with 64-bit parameters. This way, you can finally work with large numbers
  that cannot be accurately stored as a JS Number value and pass them
  correctly into C. For example, `GLib.Variant.new_int64(2n ** 62n)`.

- New API: GJS now has a standards-compliant `setTimeout()` and
  `setInterval()`. These can now be used as in web browsers, while still integrating with
  GLib's main loop.

- New API: `Cairo.Context.prototype.textExtents()` which makes the
  `cairo_text_extents()` C function available to JavaScript.

- New overrides: `GLib.MAXINT64_BIGINT`, `GLib.MININT64_BIGINT`, and
  `GLib.MAXUINT64_BIGINT` are BigInt-typed versions of `GLib.MAXINT64`

- It's now possible to use a regular `constructor()` in GObject classes
  instead of an `_init()` method.

- It's now possible to use class fields in GObject classes.

- `Gio._promisify()` now tries to guess the name of the finish function,
  if it is omitted.

- It's now possible to monkeypatch methods on the prototype of a GObject
  interface. The most common use case for this is probably promisifying
  methods on `Gio.File`, so you can now do things like
  `Gio._promisify(Gio.File.prototype, 'read_async')` without resorting
  to the `Gio._LocalFilePrototype` workaround.

- GObject interfaces are now enumerable, so you can now do things like
  `Object.keys(Gio.File.prototype)` and get a list of the methods, like
  you can with other GObject types.

- Improvements to the performance of promises, making them more
  predictable under higher load.

- Several performance and type-safety improvements.

- Closed bugs and merge requests:

  * [Mainloop 1/3] Add custom GSource for promise queueing [#1, !557,
    Evan Welsh, Marco Trevisan]
  * Upgrade to SpiderMonkey 91 [#413, !632, !687, Evan Welsh, Philip
    Chimento, Chun-wei Fan]
  * Promise rejections from signal handlers are silent [#417, !632,
    Philip Chimento]
  * Add a binding for [#48, !664, Evan Welsh, Philip
  * Object resolve should consider prototypes of GObject interfaces
    [#189, !665, Evan Welsh, Philip Chimento]
  * File corruption on file.replace_contents_async [#192, !665, Evan
  * Overriding inherited interface vfuncs clobbers base class
    implementation [#89, !671, Evan Welsh]
  * Errors in __init__.js are silenced [#343, !672, Evan Welsh]
  * Allocate structs which contain pointers [!674, Evan Welsh]
  * [Mainloop 3/3] WHATWG Timers [!677, Evan Welsh]
  * [Mainloop 2/3] Implement "implicit" mainloop which only blocks on
    unresolved imports [!678, Evan Welsh]
  * Correctly chain constructor prototypes to enable static inheritance
    [!679, Evan Welsh]
  * Upgrade CI to Fedora 34 [!683, !684, Philip Chimento]
  * Various maintenance [!685, !691, !709, !719, Philip Chimento]
  * doc: Add Junction to applications written in GJS [!688, Sonny Piers]
  * C++ argument cache [!689, Marco Trevisan, Philip Chimento]
  * Gio: Make _promisify to guess the finish function by default [!692,
    Marco Trevisan]
  * Fails to build with Meson 0.60.2 [#446, !694, !705, Jan Beich, Eli
  * doc: Add Oh My SVG to standalone applications [!695, Sonny Piers]
  * ci: Ensure forever callbacks do not leak [!698, Evan Welsh]
  * gi: Refactor resolving prototypes in GIWrapperInstance constructors
    [!699, Evan Welsh]
  * Class fields don't work with GObject classes [#331, !700, Evan
  * gi: Add enumeration hook for Interface prototypes [!701, Evan Welsh]
  * Fix Visual Studio builds on master [!706, Chun-wei Fan]
  * tools: Add iwyu-tool as a binary name for iwyu [!707, Evan Welsh]
  * gi: Allow GObject.Value boxed type in nested contexts [!708, Evan
    Welsh, Philip Chimento]
  * Implemented check for null out-params in some functions in
    context.cpp [!710, Nasah Kuma]
  * Broken links on the doc/ file [#458, !711, Andy Holmes]
  * Accept BigInt values as input for 64-bit parameters to introspected
    functions [!712, Marco Trevisan, Philip Chimento]
  * Enable top-level await [!713, Evan Welsh]
  * modules: Remove double '//' from internal module URIs [!714, Evan
  * modules: Ensure ImportError is an instance of globalThis.Error
    [!715, Evan Welsh]
  * global: Enable WeakRefs [!716, Evan Welsh]
  * global: Enable static class blocks [!717, Evan Welsh]
  * overrides: Allow users to implement construct-only props with
    getters [!718, Evan Welsh]
  * cairo: Add binding for cairo_text_extents() [!720, Philip Chimento]
  * Non-integer numbers can not be converted to (u)int64 [#459, !721,
    Philip Chimento]
  * Print error cause when logging an error [#454, !722, Philip
  * GtkCustomSorter callbacks receives undefined params [#460, !723,
    Philip Chimento]