Browser support plan—Browser support lists

The CUE browser support plan is used to guide the contents of the accompanying CUE browser support lists.

The browser support lists specify the grade of support that should be applied to each browser (and specific browser version).

Review process

The list of browsers in full support and reduced support will be reviewed periodically by the CUE Template Development Group. All other browsers receive unspecified support by default.

The review process will be based on the following decision tree:

  • If a browser is statistically prevalent it should be given full support.
    • If the vendor releases regular updates, the latest version will be given full support, earlier versions will receive unspecified support.
  • If a browser is not statistically prevalent but is important and capable2; it should receive full support (these browsers should be easy to support given their high level of standards-compliance).
  • If a browser is identified with serious bugs in its presentation or behaviour layer capabilities but maintains a statistically significant number of users, it should receive reduced support.
  • All other browsers will fall into the unspecified support category.

Thresholds will need to be determined to define 'statistically prevalent' and 'statistically significant', but the statistics should not be used in isolation. Other situation-specific arguments may factor into final review decisions.

The definitions of 'important' and 'capable' browsers will be left to the discretion of the Template Development Group to justify on a case-by-case basis 2. For example: A browser may be considered important if it provides good coverage for a particular rendering engine, operating system or device.


2 As at time of writing (March 2012) Safari may be considered important and capable. Example justification: Extending full support to Safari provides good coverage for Mac OS X operating system and presentation layer support for other WebKit based browsers such as Google Chrome and Safari for iPhone and iPad.