Firebug beta 1.0 is now available. This is by far the best toolbar available for FireFox or IE for debugging web applications. See This blog entry at Sitepoint for more details. A few of the features I really like are:
- The debugger – identifies exact line of script in error.
- The CSS inspector – shows you all ancestor css rules for elements, not just the current CSS rule, so you can see the total effect of the cascade.
- The ability to change CSS settings on the fly. For example, hover over a color, click on it, then change the RGB value to see another color – it does this for the specific area on the page, as well as in the sheet.