Browser Compatibility testing- When, Where and how it is done

Each day comes as a learning and that inspires to spread the information.For this post I will say thanks to Dr. Deepak Kaushik,One of the leading professional in the field of testing and Quality Assurance and Who is continuously  serving IT industry since last 14 years and has headed many companies and projects. He has inspire me to do more investigation on cross browser compatibility testing.

In general when ever we say browser compatibility, it shows that we are talking about the rendering of page and more after in general we think about HTML,CSS and sometime we think more ahead and talk on JavaScript and Ajax.

So first of all i would like to define Compatibility testing

Compatibility Testing is non-functional testing in which we ensure that application/website/system is capable of running on various objects like on various Browser, On various Resolution, on various Operating System, with some other application, on network.
Type of Compatibility testing

• Hardware : It checks software to be compatible with different hardware configurations .
• Operating Systems: It checks your software to be compatible with different Operating Systems like Windows , Unix , Mac OS etc.
• Software: It checks your developed software to be compatible with other software’s.For example: MS Word application should be compatible with other software like MS Outlook,MS Excel , VBA etc.
• Network: Evaluation of performance of system In network with varying parameters such as Bandwidth, Operating speed, Capacity. It also checks application  in different networks with all parameters mentioned earlier.
• Browser: It checks compatibility of your website with different browsers like Firefox , Google Chrome , Internet Explorer, Safari etc.
• Devices : It checks compatibility of your software with different devices like USB port Devices, Printers and Scanners, Other media devices and Blue tooth.
• Mobile: Checking you software is compatible with mobile platforms like Android , iOS etc.
• Versions of the software: It is verifying you software application to be compatible with different versions of software.For instance checking your Microsoft Word to be compatible with Windows 7, Windows 7 SP1 , Windows 7 SP 2 , Windows 7 SP 3.

When it is needed

• In general when algorithm of page is very complex then cross browser testing become the need of testing as soon as we can start
• When page have a lot of animation, ActiveX , Java Applet and Dynamic content then Cross browser testing should be started as soon as it is possible
• If algorithm is running on Client side then Cross Browser testing should be start early
• Other wise Cross browser testing is started when all functional testing get to end and Acceptance testing is just on the way for the final touch

Common Issues associated with Cross Browser testing

1.  Inconsistency in Page Layout
2. Inconsistency in Gride
3. Page Validation not work on certain Browser
4. Transaction is not being posted to data-base on clicking submit button or link
5. SSL certificate error that has been noticed mainly with lower version of browsers
6. Inconsistency in Tab Flow
7. Some time pagination error also occurs.

But before starting testing on browser compatibility it is sole responsbility of tester to ask certain thing with Developer of application or Website

• For which browser, application has been developed
• Ask about style sheet because every browser does not support certain style sheet version.

But there are certain thing on webpage that remain same with every Browser

• Image size would remain same with all browser
• Font color would remain same as it is mentioned in Style sheet
• Text padding also remain same but be careful if you are using some old version of IE and Netscape
• Background also remain same

For Better testing result we do these steps for better Browser compatibility testing

•  CSS and HTML and XHTML Validation : This is done to ensure that pages that has been developed are free from HTML error and are also following standards set by the W3 Consortium . For this purpose go to http://validator.w3.org/. These error show the inconsistency in page layout and structure of page along with this errors also prevents pages from search engine crawling
• Page validation :  This is checked by enabling and disabling Javascript of Browser
• Font Size Validation : Because some browser overwrite this with their default or if that font is not available on system
• All Image alignment: This is ensure the proper alignment of Image on the page
• Header and Footer should be verified with care and all text and its spacing alignment should be taken in to account for testing
• Page Alignment should be tested (Center, LHS and RHS)
• Control Alignment: Alignment of controls specially  1) Bullets 2) Radio Button 3) Check Box should be check on various Browser
  
• Page Zoom In and Out should be tested properly
• Verification of information submitted to database, if there are forms that interact with the database, It should be tested /verified on priority, should be verified that information is getting saved correctly in database
• HTML video format: Video format should be verified  because all browser does not support all format of videos example IE9 give support only to .mp4, while firefox give support to .mp4 and .webm and if we are taking Chrome then it supports almost .mp4, .webm,.ogm and some other video format
• Text Alignment : should be verified specially in DropDown
• Flash content should be tested
• CMS Compatibility should be verified: We should make sure that content management system supports
• Pages should be tested while cookies and Javascript of the browser is turned off and page should again be tested when both are on
• Verification should be done on Ajax and JQuery request

(Taken from Buzzle , W3Schools.com, https://sites.google.com/site/techsessions/Home/testing/browser-compatibility-testing, www.vietnamesetestingboard.org/)