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APPLE TOUCH ICON

PWA

A PWA icon on iOS users’ screen is called “Apple touch icon”.

WEB APP MANIFEST

PWA

In order to make the PWA installable, a Web App Manifest is required.

THEMED OMNIBOX

PWA

In order to give the user an experience more engaging, you should use the colors of your PWA in the browser’s address bar as well.

SPLASH SCREEN

PWA

If you use a custom splash screen for your PWA you will make it look more like an app.

SERVICE WORKER

PWA

A service worker should be registered in order to enable the typical features of a PWA.

MASKABLE ICON

PWA

Why manifest should have a maskable icon

TAB INDEX

Accessibility

When elements have a tabindex value greater than 0

BUTTON NAME

Accessibility

When a button does not have an accessible name

ARIA ATTRIBUTE

Accessibility

When aria attributes do not match their roles

DEPRECATIONS

Accessibility

Do not use deprecated APIs

EXTERNAL NOOPENER

Accessibility

When links to cross-origin destinations are unsafe

MANIFEST

Accessibility

Application Cache

UNLOAD LISTENER

Accessibility

How to set up correctly the unload event

PASSIVE LISTENERS

Accessibility

Improving scrolling performance by using passive listeners

JS LIBRARIES

Accessibility

JavaScript libraries noticed

CONSOLE ERROR

Accessibility

Browser errors in the console

DOCTYPE

Accessibility

Why HTML doctype is necessary

IMAGE ASPECT RATIO

Accessibility

Why natural aspect ratio needs to match image display dimensions

FORM LABEL

Accessibility

Why associate labels with form elements?

META VIEWPORT

Accessibility

How to set up correctly meta viewport

FRAME TITLE

Accessibility

Why use a title for <frame> or <iframe> elements

BYPASS

Accessibility

Why a page should contain a heading, skip link or landmark region

COLOR CONTRAST

Accessibility

How to set up a sufficient contrast ratio

LIST ITEM

Accessibility

Why should <li> be contained within <ul> or <ol> parent elements?

LIST

Accessibility

How to use lists properly

LANG VALUE

Accessibility

Why should an html element have a valid value for its lang attribute?

HTML LANG

Accessibility

Why put a lang attribute in html element

SERVER RESPONSE TIME

Speed performance

How to improve server response times (TTFB)

DOCUMENT WRITE

Speed performance

Do not use document.write

DOM

Speed performance

How to handle large DOM size

TOTAL BYTE

Speed performance

How to handle large network payloads

ANIMATED CONTENT

Speed performance

Correct use of animated content

ROBOTS.TXT

Seo content

Why robots.txt is not valid

REDIRECT

Speed performance

Avoiding too many redirects

PRECONNECT

Speed performance

Why use preconnect resource suggestions

TEXT COMPRESSION

Speed performance

How to make text compression correctly

UNUSED CSS

Speed performance

Unused CSS must be removed

MINIFY JAVASCRIPT

Speed performance

How to optimize a web page: minify JavaScript files

MINIFY CSS

Speed performance

How minify CSS to save space

OFFSCREEN IMAGES

Speed performance

How to save space with offscreen images

THIRD-PARTY

Speed performance

How to use third party JavaScript correctly

CACHE

Compressor Speed performance

How to adopt an efficient Cache Policy

RENDER BLOCKING

Compressor Speed performance

Delete render-blocking resources

FONT DISPLAY

Speed performance

How to be sure that text keeps visible during page loading

BOOTUP

Speed performance

JavaScript Execution Time: how to reduce it

BREAKDOWN

Speed performance

How to minimize Main Thread Work

TOTAL BLOCKING TIME

Speed performance

What is the Total Blocking Time parameter?

CUMULATIVE LAYOUT SHIFT

Speed performance

What is the Cumulative Layout Shift?

LARGEST CONTENTFUL PAINT

Speed performance

What is the Largest Contentful Paint parameter?

MAX POTENTIAL FIRST INPUT DELAY

Speed performance

What is the Max Potential First Input Delay parameter?

INTERACTIVE

Speed performance

What is the Time To Interactive Parameter?

SPEED INDEX

Speed performance

How to improve speed index

FIRST CONTENTFUL PAINT

Speed performance

What is the First Contentful Paint parameter?

PAGE DIMENSION

Seo content

How to reduce network payload

CHARSET

Seo content

What is the meaning of charset?

IMAGE RESOLUTION

Seo content

What is the meaning of image resolution?

RESPONSIVE IMAGES

Seo content

What is a responsive image?

HREF LANG

Seo main factors

What is hreflang used for?

VIEWPORT

Seo main factors

What is viewport in HTML?

SERVER STATUS

Seo main factors

Why HTTP status code is important?

CRAWLABLE ANCHORS

Seo main factors

How do I make a page crawlable?

CRAWLABLE

Seo main factors

What does it mean to be crawlable?

CHARSET DECLARATION

Seo main factors

What is charset declaration encoding?

CANONICAL

Seo main factors

What does canonical link do?

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