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August 22, 2017

All chapters

• Applicable pages, applicables sections

  All instances of "Timeline profiler," "Timeline panel," or "Timeline tool," should read "Performance panel," because Chrome has renamed the Timeline Tool.

Chapter 1

• Page 4, Section 1.1.2

  "it talks to a server in a language called Hypertext Transfer Protocol" should read "it talks to a server over a protocol called Hypertext Transfer Protocol"

  "amount of time it takes for a response to arrive in full" should read "amount of time it takes for a response to reach the client"

  "As of July 2016, only approximately 8.5% of all web servers are using HTTP/2" should be updated to reflect new statistics. It should read "As of June 2017, approximately 15% of all web servers are using HTTP/2"

• Page 10, Section 1.3

  "For a small site" should read "For a relatively unknown site"

  "because of mechanisms" should read "via mechanisms"

• Page 17, Section 1.4.2

  "in the software's httpd.conf configuration file." should read "in Apache web server's httpd.conf configuration file."

  "Some allow more configuration than others." should read "Some allow more (or less) configuration than others."

• Page 18, Section 1.4.3

  "Image compression has come a long way" should read "Image optimization has come a long way"

  "Today's algorithms" should read "Today's image optimization methods"

  Replace figure 1.13 with the image provided in img/1.13.png.

Chapter 2

• Page 25, Section 2.1.2

  "server push fixes this antipattern" should read "server push is an alternative to this antipattern"

• Page 37, Section 2.4.3

  "you'll see a range of red frames" should read "you may see a range of red frames (depending on your machine's processing power)"

• Page 37, Figure 2.21

  Replace figure 2.21 with the image provided in img/2.21.png.

  Delete "Note the explicit warning and the low frame rate." in the figure caption.

• Page 38, Section 2.4.3

  "you’ll see a lot of events labeled Timer Fired" should read "you'll see one or more events labeled Timer Fired"

  "you’re seeing a lot of these" should read "you’re seeing these events"

Chapter 3

• Page 54, Section 3.1.1

  "culls unnecessary styles" should read "culls unnecessary rules"

• Page 71, Section 3.3.5

  "are so fast" should read "are fast enough"

• Page 72, Section 3.3.6

  Delete "The reason for this is that browsers are fast at rendering pages."

• Page 79, Section 3.4.1

  The CSS declaration for the .box selector is missing the closing curly brace (})

Chapter 4

• Page 83, Section 4.1

  "that enables you to rethink" should read "that rethinks"

• Page 84, Section 4.1.1

  Delete "in the case of desktop devices,"

• Page 85, Section 4.1.2

  Delete "on a page's initial load"

  "front-end development technology" should read "front-end development techniques"

• Page 86, Section 4.2.1

  Delete "The <link> tag takes advantage of caching to optimize return visits."

• Page 87, Section 4.2.1

  "the rel value of the <link>" should read "the rel value of the <link> tag"

• Page 90, Section 4.3.2

  Delete "in descending order,"

• Page 97, Section 4.3.3

  "such as Safari" should read "such as Internet Explorer" (Safari 11 will add preload support. IE never will, since Edge succeeds it.)

• Page 99, Section 4.5

  "This is how to inline" should read "Listing 4.2 shows you how to inline"

• Page 101, Section 4.7

  "eliminate this behavior" should read "mitigate this behavior"

  "sidestep the effects" should read "mitigate the effects"

Chapter 5

• Page 107, Section 5.2.1

  "unless transparency support" should read "unless full transparency"

• Page 107, Figure 5.7 caption

  "is throttled down" should read "is quantized to"

• Page 108, Section 5.2.2

  "These images use a vector artwork format." should read "SVG is a vector artwork format."

  "best possible visual integrity every time." should read "best possible visual integrity for all displays."

• Page 109, Table 5.1

  "Accommodates any image format" should read "Accommodates any type of content"

• Page 117, Section 5.4.1

  "is this simple code." should read "is this simple bit of CSS."

• Page 127, Section 5.4.5

  Both <img> tag code snippets have a period after the closing angle bracket (>). This period should not be there.

Chapter 7

• Page 167, Table 7.2

  "All except for and IE8 and below" should read "All except for IE8 and below."

• Page 168, Section 7.1.2

  In the callout box, "pay use rights" should read "pay usage rights"

• Page 169, 171, Listing 7.1, 7.2

  format("truetype "); should read format("truetype"); (There's a superfluous space in the format string).

• Page 170, Section 7.1.2

  "Safari uses the WOFF file." should read "Safari (on some older versions of macOS) uses the WOFF file."

• Page 178, Section 7.3.2

  "Then, you'll discuss a fallback" should read "Then, you'll learn about a fallback"

• Page 182, Section 7.3.2

  Consider striking the entire "FALLBACKS FOR OLDER BROWSERS" section. unicode-range support is over 90%.

• Page 194, Section 7.5

  Delete "If you need to selectively serve font subsets, you can write a script that can be used to serve subsets when unicode-range isn't an option."

Chapter 8

• Page 208, Listing 8.3

  The last line is missing a closing parentheses before the semicolon (e.g., });)

• Page 216, Listing 8.3.7

  "by examining the network requests for that browser." should read "by examining network requests in that browser's developer tools."

• Page 218, Listing 8.4.2

  "this example has limitations" should read "this example isn't ideal"

Chapter 10

• Page 234, Section 10.1

  "poorly compressed configurations" should read "poor compression configuration"

• Page 249, Tip Box entitled "Creating a Security Exception"

  "isn't signed by a recognized authority" should read "isn't issued by a recognized certificate authority"

• Page 255, Section 10.2.1

  "You might use a CDN" should read "You might use a CDN (Content Delivery Network)". Would be good for clarity to spell out the acronym.

• Page 256, Section 10.2.1

  Delete "This directive passes the asset through to the user."

• Page 256, Section 10.2.2

  In the Table 10.1 caption, "should be u" should read "should be used."

  In Table 10.1, the row Asset type row labeled "CSS and JavaScript" should strike ,stale-while-revalidate=86400 from its "Cache-Control" header value.

• Page 257, Section 10.2.2

  "aggressively revalidated" should read "aggressively cached"

• Page 262, Section 10.3.1

  "I'll let the graph in figure 10.15" should read "I'll let figure 10.15"

• Page 263, Section 10.3.1

  "three to four times faster" should read "much faster"

• Page 267, Section 10.4

  "As HTML has matured, features have been added to the language" should read "As browsers have matured, features have been added to them"

• Page 269, Section 10.4.2

  The code snippet reading:
  <link rel="prefetch" href="https://code.jquery.com/jquery-2.2.3.min.js">

Should read:
  
  <link rel="prefetch" href="https://code.jquery.com/jquery-2.2.3.min.js" as="script">
  
  
  Similarly, the code snippet reading:
  
  Link: <https://code.jquery.com/jquery-2.2.3.min.js>; rel=prefetch
  
  Should read:
  
  Link: <https://code.jquery.com/jquery-2.2.3.min.js>; rel=prefetch; as=script

• Page 271, Section 10.4.2

  "and causes no ill effects when omitted." should read "but omitting it is detrimental, because the browser will download the asset twice if as isn't present."

  "uses the same HTTP header syntax" should read "uses the same HTTP header syntax in some HTTP/2 implementations"

• Page 271, Section 10.4.3

  Ignore this entire section. prerender is deprecated and will enventually be unavailable.

Chapter 11

• Page 275, Introduction

  "be better performing on" should read "better accommodate"

• Page 276, Section 11.1.1

  "and nonsecure websites" should read "and a lack of a mandate for HTTPS"

  "typically, six at once" should read "often six at once, but varies by browser)

• Page 277, Section 11.1.1

  Delete "of six per domain"

  "twelve requests" should read "twice as many requests"

  Delete "With three, up to eighteen requests could be accommodated simultaneously"

• Page 279, Section 11.1.2

  "you no longer have" should read "you may no longer have"

• Page 288, Section 11.2.2

  Delete ", except that bundling on HTTP/2-driven websites isn't optimal"

• Page 289, Section 11.2.2

  "you don't need it" should read "you may not need it"

• Page 290, Section 11.3.1

  "You can push as many assets as you'd like." should read "You can push as many assets as you'd like (though you can push too many assets)."

• Page 291, Section 11.3.2

  "The as attribute is there only to inform the browser of the nature of the pushed content, and isn't necessary for Server Push to work." should read "The as attribute informs the browser of the nature of the pushed content."