JavaScript (edit)

Getting the ID of the element that fired an event

How to Use Different CSS Style Sheets For Different Browsers (and How to Hide CSS Code from Older Browsers) (HAY)

Handling CSS prefixes

Another set of problems comes with CSS prefixes — these are a mechanism originally used to allow browser vendors to implement their own version of a CSS (or JavaScript) feature while the technology is in an experimental state, so they can play with it and get it right without conflicting with other browser's implementations, or the final unprefixed implementations. So for example:

  • Mozilla uses -moz-
  • Chrome/Opera/Safari use -webkit-
  • Microsoft uses -ms-

Handling common HTML and CSS problems

Learn about Flexbox and CSS Grids

Advanced Cross-Browser Flexbox

CSS Examples

JavaScript in iFrame

This is small solution that works in all browsers even IE8:

var elem = document.activeElement; ...