Merge branch 'master' of https://github.com/javascript-tutorial/en.javascript.info

# Conflicts:
#	1-js/01-getting-started/2-manuals-specifications/article.md
#	1-js/05-data-types/07-map-set-weakmap-weakset/article.md
#	1-js/05-data-types/10-date/3-weekday/solution.md
#	1-js/07-object-oriented-programming/06-prototype-methods/article.md
#	1-js/09-classes/01-class/article.md
#	1-js/09-classes/05-extend-natives/article.md
#	1-js/11-async/03-promise-chaining/article.md
#	1-js/12-generators-iterators/1-generators/01-pseudo-random-generator/solution.md
#	1-js/12-generators-iterators/1-generators/article.md
#	1-js/13-modules/03-modules-dynamic-imports/article.md
#	2-ui/1-document/11-coordinates/coords.png
#	2-ui/1-document/11-coordinates/coords@2x.png
#	2-ui/1-document/11-coordinates/document-window-coordinates-scroll.png
#	2-ui/1-document/11-coordinates/document-window-coordinates-scroll@2x.png
#	2-ui/1-document/11-coordinates/document-window-coordinates-zero.png
#	2-ui/1-document/11-coordinates/document-window-coordinates-zero@2x.png
#	2-ui/99-ui-misc/01-mutation-observer/article.md
#	6-data-storage/01-cookie/article.md
#	6-data-storage/02-localstorage/article.md
#	8-web-components/2-custom-elements/article.md
#	8-web-components/5-slots-composition/article.md
#	8-web-components/6-shadow-dom-style/article.md
#	8-web-components/7-shadow-dom-events/article.md
#	figures.sketch

Author: mehradsadeghi

1-js/04-object-basics/01-object/article.md

@@ -49,7 +49,7 @@ We can add, remove and read files from it any time.
 Property values are accessible using the dot notation:
 
 ```js
-// get fields of the object:
+// get property values of the object:
 alert( user.name ); // John
 alert( user.age ); // 30
 ```
@@ -105,7 +105,6 @@ That's because the dot requires the key to be a valid variable identifier. That
 
 There's an alternative "square bracket notation" that works with any string:
 
-
 ```js run
 let user = {};
 
@@ -130,7 +129,7 @@ let key = "likes birds";
 user[key] = true;
 ```
 
-Here, the variable `key` may be calculated at run-time or depend on the user input. And then we use it to access the property. That gives us a great deal of flexibility. The dot notation cannot be used in a similar way.
+Here, the variable `key` may be calculated at run-time or depend on the user input. And then we use it to access the property. That gives us a great deal of flexibility.
 
 For instance:
 
@@ -146,6 +145,17 @@ let key = prompt("What do you want to know about the user?", "name");
 alert( user[key] ); // John (if enter "name")
 ```
 
+The dot notation cannot be used in a similar way:
+
+```js run
+let user = {
+  name: "John",
+  age: 30
+};
+
+let key = "name";
+user.key // undefined
+```
 
 ### Computed properties
 
@@ -222,9 +232,10 @@ As we see from the code, the assignment to a primitive `5` is ignored.
 
 That can become a source of bugs and even vulnerabilities if we intend to store arbitrary key-value pairs in an object, and allow a visitor to specify the keys.
 
-In that case the visitor may choose "__proto__" as the key, and the assignment logic will be ruined (as shown above).
+In that case the visitor may choose `__proto__` as the key, and the assignment logic will be ruined (as shown above).
 
 There is a way to make objects treat `__proto__` as a regular property, which we'll cover later, but first we need to know more about objects.
+
 There's also another data structure [Map](info:map-set-weakmap-weakset), that we'll learn in the chapter <info:map-set-weakmap-weakset>, which supports arbitrary keys.
 ````
 

1-js/05-data-types/03-string/article.md

@@ -314,7 +314,7 @@ if (str.indexOf("Widget") != -1) {
 
 One of the old tricks used here is the [bitwise NOT](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Bitwise_Operators#Bitwise_NOT) `~` operator. It converts the number to a 32-bit integer (removes the decimal part if exists) and then reverses all bits in its binary representation.
 
-For 32-bit integers the call `~n` means exactly the same as `-(n+1)` (due to IEEE-754 format).
+In practice, that means a simple thing: for 32-bit integers `~n` equals `-(n+1)`.
 
 For instance:
 
@@ -345,7 +345,7 @@ It is usually not recommended to use language features in a non-obvious way, but
 
 Just remember: `if (~str.indexOf(...))` reads as "if found".
 
-Technically speaking, numbers are truncated to 32 bits by `~` operator, so there exist other big numbers that give `0`, the smallest is `~4294967295=0`. That makes such check is correct only if a string is not that long.
+To be precise though, as big numbers are truncated to 32 bits by `~` operator, there exist other numbers that give `0`, the smallest is `~4294967295=0`. That makes such check is correct only if a string is not that long.
 
 Right now we can see this trick only in the old code, as modern JavaScript provides `.includes` method (see below).
 
@@ -519,7 +519,7 @@ alert( str );
 // ¡¢£¤¥¦§¨©ª«¬­®¯°±²³´µ¶·¸¹º»¼½¾¿ÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖ×ØÙÚÛÜ
 ```
 
-See? Capital characters go first, then a few special ones, then lowercase characters.
+See? Capital characters go first, then a few special ones, then lowercase characters, and `Ö` near the end of the output.
 
 Now it becomes obvious why `a > Z`.
 
@@ -631,10 +631,12 @@ This provides great flexibility, but also an interesting problem: two characters
 For instance:
 
 ```js run
-alert( 'S\u0307\u0323' ); // Ṩ, S + dot above + dot below
-alert( 'S\u0323\u0307' ); // Ṩ, S + dot below + dot above
+let s1 = 'S\u0307\u0323'; // Ṩ, S + dot above + dot below
+let s2 = 'S\u0323\u0307'; // Ṩ, S + dot below + dot above
 
-alert( 'S\u0307\u0323' == 'S\u0323\u0307' ); // false, different characters (?!)
+alert( `s1: ${s1}, s2: ${s2}` );
+
+alert( s1 == s2 ); // false though the characters look identical (?!)
 ```
 
 To solve this, there exists a "unicode normalization" algorithm that brings each string to the single "normal" form.