W3C mobileOK Checker

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Report summary

File checked

Some tests cannot be run in file upload mode

The mobileOK Checker cannot retrieve CSS stylesheets, images and links that use addresses relative to the resource under test in file upload mode. Some tests cannot be run or can only be run partially as a result. For instance, the total size of the page is not accurrate if images cannot be retrieved. Similarly, tests that apply at the HTTP level, e.g. to ensure that the content is served with appropriate caching directives cannot be checked.

Thus this report is not complete and additional failures may be reported if the content is checked using the Validate by URI mode.

Result: 21%

mobileOK score: 21%

Failures per severity

critical: 1
severe: 1
medium: 2
low: 2

Failures per category

Rely on Web standards: 2
Stay away from known hazards: 1
Keep it small: 1
Think of users on the go: 1
HTTP errors: 1

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Page Size: 2.6KB

The total size of the page is 2.6KB
(document: 2.6KB)

Size	Type	URI
2.6KB (*)	document	Resource under test

(*) Size of the HTTP error message received.

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Network usage: 2 requests

2 requests needed to render the page in a Web browser
(document: 1 - images: 1)

Type	URI
document (*)	Resource under test
image (*)	images/cb2.jpg

(*) HTTP error message received.

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Severity: ; category: ; description: The document contains a frame, frameset or iframe element ; Best Practice: NO FRAMES
Why?

Most mobile browsers simply don't support frames. Besides, given the lack of pointing devices on most mobile devices, frames would result in a extremely poor user experience.

How?

Remove frames, and use a CSS-based layout instead.
Where?

Triggered 3 times by the resource under test:

Line 37

… <iframe allowfullscreen="allowfullscreen" src="https://www.youtube.com/embed/mqqyAlr50fU" />

Line 43

… <iframe allowfullscreen="allowfullscreen" src="https://www.youtube.com/embed/RUQ5OPtG5W4" />

Line 49

… <iframe allowfullscreen="allowfullscreen" src="https://www.youtube.com/embed/_8Xpjy0GGEI" />
More information

Severity: critical

Most mobile devices will not be able to render (part of) the page or will not be able to render the page in a reasonable time frame. Critical failures should be addressed first!

Category: Stay away from known hazards

Thoughtful design can help reduce usability problems due to small screens and keyboards, and other features of mobile devices.

Best practice: NO_FRAMES

Do not use frames.

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Severity: ; category: ; description: The certificate is invalid. ; Best Practice:

Why?

Invalid certificates will be rejected by mobile browsers, de facto preventing the rendering of the page.

How?

This usually means that the certificate could not be retrieved or that the cryptographic algorithm used for the key exchange is not widely supported.

Where?

Triggered by https://jquery.com/.

More information

Severity: severe

Most mobile devices should render the page but the user experience is strongly impacted.

Category: HTTP errors

The mobileOK Checker could not retrieve some of the resources required to run the tests or has found broken links.

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Severity: ; category: ; description: There is no page title ; Best Practice: PAGE TITLE

Why?

The page title is displayed by most mobile devices on top of the screen, and to identify bookmarks. Given the limited size of mobile screens, it is an essential piece of information for the user.

How?

Define a short but descriptive title.

Where?

Triggered by the resource under test.

More information

Severity: medium

A mobile constraint has not been taken into account or the page relies on implicit hypotheses that could turn out to be wrong. For instance, a more conservative use of the network is possible (e.g. whitespaces account for more than 10% of the size of the page) or the character encoding is not explicitly set in the page.

Category: Think of users on the go

Web users on the go want compact information when time is short and distractions many.

Best practice: PAGE_TITLE

Provide a short but descriptive page title.

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Severity: ; category: ; description: More than 25% of the page characters are extraneous (whitespaces or comments) ; Best Practice: MINIMIZE

Why?

Given the limitations of mobile networks, sending extraneous whitespaces and comments make pages slower and more costly to load.

How?

Remove useless whitespaces and comments by adding a cleaning step in the publication process (e.g. through tidy).

Where?

Triggered by the resource under test.

More information

Severity: medium

A mobile constraint has not been taken into account or the page relies on implicit hypotheses that could turn out to be wrong. For instance, a more conservative use of the network is possible (e.g. whitespaces account for more than 10% of the size of the page) or the character encoding is not explicitly set in the page.

Category: Keep it small

Smaller sites make users happier by costing less in time and money.

Best practice: MINIMIZE

Use terse, efficient markup.

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Severity: ; category: ; description: The document does not validate against XHTML Basic 1.1 or MP 1.2. ; Best Practice: VALID MARKUP
Why?

The document is invalid XHTML or uses elements or structures that are not allowed in the XHTML Basic 1.1 specification. This is likely to be problematic for mobile browsers who are more sensitive to the structure of the content than desktop browsers.

How?

Check the page with the W3C Markup Validator
While unknown elements are likely to be ignored by browsers, a simple syntax error may invalidate the document to the point where browsers cannot render it anymore. Also bear in mind that checks were run against a tidied version of the document. The tidying process may have modified the structure and semantics of the original document and may have either created new problems or fixed existing ones.
Where?

Triggered 5 times by the resource under test:

Line 8, Column 8 — The content of element type "head" is incomplete, it must match "((script|style|meta|link|object)*,((title,(script|style|meta|link|object)*,(base,(script|style|meta|link|object)*)?)|(base,(script|style|meta|link|object)*,(title,(script|style|meta|link|object)*))))".

Line 11, Column 31 — Element "header" is not allowed.

Line 19, Column 28 — Element "article" is not allowed.

Line 20, Column 58 — Element "aside" is not allowed.

Line 23, Column 303 — The entity name must immediately follow the '&' in the entity reference.
More information

Severity: low

Useful improvements are possible.

Category: Rely on Web standards

In the highly fragmented market of devices and browsers, standards are the best guarantee for interoperability.

Best practice: VALID_MARKUP

Create documents that validate to published formal grammars.

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Severity: ; category: ; description: The DOCTYPE declaration is missing or is syntactically invalid ; Best Practice: VALID MARKUP

Why?

The DOCTYPE declaration at the top of an HTML document helps browsers optimize the parsing and rendering of the page. See Don't forget to add a doctype.

How?

Add the appropriate DOCTYPE declaration to your document. If the document contains a syntactically invalid DOCTYPE declaration, refer to the Document Type Definition production rules to fix the declaration.
This message may also be reported when the XML declaration of the document is invalid or when the XML declaration does not appear right at the start of the document. Refer to the failure message "The document does not validate against XHTML Basic 1.1 or MP 1.2." in this report for more details.

Where?

Triggered by the resource under test.

More information

Severity: low

Useful improvements are possible.

Category: Rely on Web standards

In the highly fragmented market of devices and browsers, standards are the best guarantee for interoperability.

Best practice: VALID_MARKUP

Create documents that validate to published formal grammars.

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Source listing

The W3C mobileOK Checker follows the W3C mobileOK Basic Tests 1.0 standard and uses specific HTTP headers to retrieve resources as if it were a mobile device. As a result, tests may not be run against the content one may see when the resource is viewed on a regular desktop browser.

Source listing of the resource under test
1. <!doctype html>
2. <html>
3. <head>
4. 
5. 
6. 
8. </head>
10. <body>
11. <header class="w3-container">
12. <p>ProfBurnett.com</p>
13. </header>
15. 
16. 
17. 
19. <article class="w3-row">
20. <aside id="aside-left" class="w3-container w3-third">
21. <h2>Welcome to ProfBurnett.com</h2>
22. <img src="images/cb2.jpg" width="75" height="75" alt="Carl Burnett" />
23. <p>Thank you for visiting my site. Look around, kick the tires and see what courses I'm teaching. Check out my CV above and enjoy the site! This is a HTML5 responsive web design (RWD) site. . It features the <a href="http://www.w3schools.com/w3css/default.asp">W3.CSS framework</a>, and HTML5 & CSS3. It also uses <a href="https://jquery.com/">jQuery, and jQuery UI</a>, the JavaScript frameworks, and other modular RWD components that support lightweight design and interoperability on desktop, tablet, and mobile devices.</p>
24. </aside>
25. <section class="w3-container w3-third">
26. 
27. 
28. 
29. </aside>
30. </article>
31. <hr>
32. <section id="videowall" class="w3-row">
33. <h2>Tech Videowall</h2>
34. <aside id="aside-left" class="w3-container w3-third">
35. <h4>2016 Tech Trends to Watch<br>Goldman Sachs</h4>
36. 
37. <iframe src="https://www.youtube.com/embed/mqqyAlr50fU" allowfullscreen></iframe>
38. 
39. </aside>
40. <aside id="aside-left" class="w3-container w3-third">
41. <h4>5 Technologies that could change your life in 2016<br>techradar</h4>
42. 
43. <iframe src="https://www.youtube.com/embed/RUQ5OPtG5W4" allowfullscreen></iframe>
44. 
45. </aside>
46. <aside id="aside-right" class="w3-container w3-third">
47. <h4>HR Tech Trends for 2016<br>TopDogHR</h4>
48. 
49. <iframe src="https://www.youtube.com/embed/_8Xpjy0GGEI" allowfullscreen></iframe>
50. 
51. </aside>
52. </section>
53. <hr>
55. 
56. 
57. 
59. 
60. 
61. 
62. </article>
63. <footer>
64. <p>© 2016, ProfBurnett.com Silver Spring, MD 20904</p>
65. </footer>
66. </body>
67. </html>

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W3C Mobile Web Initiative sponsored by MobiWeb 2.0 FP7 EU project

Validators donation program

This is the W3C mobileOK Checker v1.4.2
This work is part of the MobiWeb 2.0 project supported by the European Union's 7th Research Framework Programme (FP7).
The checker is based on the open source mobileOK checker library developed by the Mobile Web Best Practices working group.

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