Page 19 of 22 of the Unsolicited Advice Archives

1. Supporting and detecting @supports

   Opera recently added support for the @supports feature of the CSS Conditional Rules Module. Using @supports offers a native way to feature-test support for CSS properties and values. @supports (display: flex){ /* Include flexible box styling here */ } You can also test for negation, and provide rules for cases when a feature

2. Make fewer DOM updates with createDocumentFragment()

   During a recent conversation about some code I've released, the other party asked me why I didn't use a document fragment. I think my reaction was more or less "What, well, um, I don't know, so I'm just going to bullshit and pretend I know what you're talking about or

3. Meet the datalist element

   UPDATE: Browsers vary a bit in how they render datalists based on the type of form input. Eiji Kitamura has a demo that illustrates how they all work. One of my favorite parts of HTML5 forms is the datalist element. Opera added support in version 9.0. Support in

4. Array.prototype.map() versus Array.prototype.forEach()

   Both map() and forEach() are native JavaScript methods of the Array object. Both methods accept up to two parameters: a required callback function, and an optional argument that will become the object referred to by this within the callback. That last part is confusing, so let me illustrate with some

5. 

   Striped border bug on transformed elements in ≤ Opera 12.02

   Opera's border rendering on elements with a rotate transform applied. Opera 12.02 (and older...

6. 

   Toying with CSS Filter Effects

   I spent this weekend getting my feet wet with CSS Filter Effects, in particular, the filter...

7. Opera Mini and JavaScript

   'Opera Mini is one of the world’s foremost mobile browsers, which runs on pretty much any device, even low-powered ones. It is a proxy-based browser, which has many advantages, including reducing the size of pages downloaded onto the user’s phone by up to 90%. On the downside, JavaScript can behave in unexpected ways when requested by Opera Mini. In this article we’ll discuss exactly what this means for your development work, in detail.'

8. Testing for CSS 3D Transforms Support

   Support for 3D CSS Transforms has made it into most browsers in an experimental form. Opera's support, however, is still busy baking. Unfortunately, 2D and 3D transforms share at least one property in common: transform (though prefixes are still required for now). Testing for it won't exactly tell you whether

9. Introduction to XMLHttpRequest Level 2

   'XMLHttpRequest is the primary technology that allows us to do Ajax-style updates to our pages — essentially, more dynamic content updates that don’t require page reloads. The XHR1 spec (and earlier versions) worked okay but had a number of shortcomings. The new version — XHR2 — addresses many of those shortcomings; in this article we’ll look at how, providing an overview and explanatory examples of all the main features.'