Xah Web Dev Blog 2021-01


CSS Selector Syntax

WebGL Demo: Brisk Hindsight

JS: Reflect.set
added example using this binding.

JS: Getter/Setter Properties
added a section on this binding.

JS: Reflect.construct
major rewrite.

Buy Followers Scam

Access Property
minor format update

CSS Text Alignment, Justification
minor update

and minor updates to

minor updates

See also: null

CSS: Overflow Wrap

minor updates. interactive css code generators.

major update to the JavaScript Object Reference section. Mostly formatting issues.

Web Domain Farm Spam

change Object.getPrototypeOf to Reflect.getPrototypeOf

See also:

random articles, reviewed

updated. Empty array is error, unless there's 2nd arg

What is a Browser

HTML Entity List
minor update.


HTML Frameset Tutorial
added chrome browser screenshot

now, you can buy my JavaScript tutorial using amazon. Buy JavaScript in Depth

spectacular plane curves in JavaScript, by mathematician Hermann Karcher http://virtualmathmuseum.org/Curves/index.html

great pong game in JavaScript

HTML: Input Number Field
minor update.

all updated.


Source Code Encoding

minor update

minor updates.

major updates.

minor updates


minor updates

JavaScript NaN === NaN?

JavaScript try this in your browser console NaN === NaN did you guess right?


HTML Video Tag
minor update

JavaScript what's the difference between isNaN(num) and Number.isNaN(num)

JavaScript trivia.
what's the difference between

answer at

the idiocy of programer nerds and typographers

Font Size problem

Firefox button size changes background color

idiotic Firefox. if you change button size, it changes the background color.

button size test 2020-04-22 rk6br
button size test 2020-04-22
<li><button style="font-size:1rem;" type="button">1</button></li>
<li><button style="font-size:1.1rem;" type="button">2</button></li>
<li><button style="font-size:1.2rem;" type="button">3</button></li>


the Map Object Tutorial

CSS: Letter Spacing, Word Spacing

HTML: Definition List dl dt dd
minor update.

CSS: “:before”, “:after”
minor update

New Version of JavaScript in Depth

new version is out. I am sending to past buyers.

If you haven't already, buy at
Buy JavaScript in Depth

Master JavaScript today.

random tip today CSS Selector Syntax
when i work on my site, i use my own tutorials and references often so i was just looking at CSS to see how can i format table better for small screen

Intro to Event-Based Programing
minor update

User Interface Design
new nav panel.

brave browser still crashes on macOS catalina. latest version

w3c and whatwg finally merged their html spec

w3c whatwg merge html spec 2020-03-09 m533q
w3c whatwg merge html spec 2020-03-09

w3c and whatwg finally merged their html spec. No more diff specs. Also, many links to w3c html spec now redirect to whatwg. e.g. https://www.w3.org/TR/html/syntax.html#void-elements

major update to my JavaScript tutorial's navigation panel. Have a look
JavaScript in Depth


Google's webp is a virus

Google's webp is a virus. It's now used by amazon when you are in chrome. Firefox now supports webp too. Apple still doesn't. Not in Safari, not in image preview, etc.