Difference between Firefox 3 and Firefox 4?

Question

I was thinking about upgrading to Firefox 4 (Firefox 3.6.15 is currently running - don't hold on to a specific software issue!) And had some problems when it comes to web development.

My only problem is if there are compatibility issues (CSS / HTML) or quirks between them. I would really like to see something like the 3px interval when using Firefox 4 on the same website versus 0px using Firefox 3 (almost like IE6 vs IE7 vs IE8 fiasco if you get my drift).

Ultimately, I just check to see if Firefox 4 is common with displaying a website / web application with an updated "engine" (which I expect).

Thoughts? Does anyone compare at this level? And I'm not just talking about things, as at the CSS Reset level, especially since I think about these combinations.

I hope that I make my concerns somewhat clear. I could not find any comparisons, except for the list of improvements, in FF4 (over FF3), I do not want to do this with a software issue, but should I know about any output changes that I miss when updating. I don’t want to miss critical differences when it comes to browser development and compatibility for the client.

Thanks.

Answer 1

Even IE6 / IE7 / IE8 and other browsers are not as large as you figured out; Errors in older versions of IE with strange differences in intervals were caused mainly by the fact that websites make the browser work in Quirks mode (which corresponds to its name), and not according to the standard. If you are in standard mode, browsers largely comply with the same rules, although with fewer features in older versions (much less features with IE6).

With this in mind, upgrading from FF3.6 to FF4.0 should not present you with problems with existing sites written with FF3.6 in mind (and in standard mode in general).

The only important warning I know with FF4 is that they removed the -moz-binding CSS function. This (or rather, it was) a Firefox-specific CSS feature (i.e. non-standard) that allowed you to associate a XUL template with an HTML element using CSS. XUL is the XML interface definition language that the Firefox user interface is written in (as well as other applications from Mozilla). They eliminate the ability to link to it directly from a web page for security reasons.

This question should not apply to anyone at all - if you still adhered to standards, you would never use it.

However, there is one way that it has been used quite widely: how to hack the browser so that Firefox supports ellipsis. All other browsers support CSS text-overflow:ellipsis; but Firefox does not. Even FF4 does not support it. Someone managed to crack the way to do this using -moz-binding , and many sites have used it since then. This hack will stop working in FF4.

See my question on this topic here: text-overflow: ellipsis in Firefox 4? (and FF5)

But apart from this, one thing, pretty much everything else new in Firefox 4 - of course, in terms of the rendering mechanism - is a gradual update from FF3.6, so existing sites should continue to work without changes.

Answer 2

https://developer.mozilla.org/en/Firefox_4_for_developers

Answer 3

You can run both versions in the same field, at least for testing.

http://www.thewindowsclub.com/how-to-run-firefox-3-and-firefox-4-simultaneously-in-windows

I think you cannot do this very effectively with other browsers. (e.g. IE or Chrome with automatic updates)

Answer 4

The main differences between them will be more like new elements, properties and APIs, rather than the basic properties, as you mentioned. Any minor design or layout issues were resolved long ago or, if someone had to be fixed, probably rarely. This is not like IE, where there are problems not only between versions, but also inside versions.

Answer 5

No matter what has been published so far, be careful because I already noticed a few differences in the rendering - especially with the vertical spacing elements and the built-in list. In my case, the difference is really huge, as it affects the appearance of the top menu item. Previously, IE8, Chrome10 / 11, and FF4 all displayed it the same way, but now FF4 is a definite output. I also use html5 / html4-strict doctype. Just consider something; the transition is not as rosy as the previous posts, perhaps they would have made you believe ...