But, I assume once they RTM, they are going to make is so big and install like super super super slow. And they ironically will force  removing IE8 since they like to get crazy.

All that the IE9 preview is is the engine. There's HUGE amounts of the browser missing there. And the engine has been capable of IE5, 7 and 8 all along. So it's not like their incuding a bunch of code that the other browsers didn't.

Dodo said:

There's no difference in the rendering engine of IE5.5 and IE6, as far as I know there were only security improvements (SSL and a lot of warning mesage boxes) added to the browser part.

Actually IE6 changed things massively from IE5, including massive changes in support for CSS2 features.

I understand "IE6" isn't an option because IE7 Compatibility Mode is essentially the same as IE6 sans serious layout bugs. These aren't mere differences in rendering that poorly made applications might rely upon, but actually broken rendering that was fixed in IE7 (they spent their time fixing this in IE7 rather than completing CSS2.1 support, that's what they did in IE8). If an application was written against IE6 it's going to work in IE7 compatibility mode.

But the inclusion of IE5 mode is interesting, I wonder if it's just a rebranding for IE6's own Quirks Mode, I don't believe Microsoft would actively put effort into reproducing IE5's rendering behaviour: IE5 was only out for just over a year and a bit before IE6 came out (not forgetting IE5.5 in the middle) and IE6 was widely accepted by enterprises.

W3bbo said:

Dodo said:

*snip*

Actually IE6 changed things massively from IE5, including massive changes in support for CSS2 features.

 

I understand "IE6" isn't an option because IE7 Compatibility Mode is essentially the same as IE6 sans serious layout bugs. These aren't mere differences in rendering that poorly made applications might rely upon, but actually broken rendering that was fixed in IE7 (they spent their time fixing this in IE7 rather than completing CSS2.1 support, that's what they did in IE8). If an application was written against IE6 it's going to work in IE7 compatibility mode.

 

But the inclusion of IE5 mode is interesting, I wonder if it's just a rebranding for IE6's own Quirks Mode, I don't believe Microsoft would actively put effort into reproducing IE5's rendering behaviour: IE5 was only out for just over a year and a bit before IE6 came out (not forgetting IE5.5 in the middle) and IE6 was widely accepted by enterprises.

Indeed, I have a sneaking suspicion that IE5 means Quirks mode, because it's probably more understandable that way for the less savvy web developers out there (i.e. the ones who're still writing pages in/for quirks mode)

W3bbo said:

Dodo said:

*snip*

Actually IE6 changed things massively from IE5, including massive changes in support for CSS2 features.

 

I understand "IE6" isn't an option because IE7 Compatibility Mode is essentially the same as IE6 sans serious layout bugs. These aren't mere differences in rendering that poorly made applications might rely upon, but actually broken rendering that was fixed in IE7 (they spent their time fixing this in IE7 rather than completing CSS2.1 support, that's what they did in IE8). If an application was written against IE6 it's going to work in IE7 compatibility mode.

 

But the inclusion of IE5 mode is interesting, I wonder if it's just a rebranding for IE6's own Quirks Mode, I don't believe Microsoft would actively put effort into reproducing IE5's rendering behaviour: IE5 was only out for just over a year and a bit before IE6 came out (not forgetting IE5.5 in the middle) and IE6 was widely accepted by enterprises.

IE5 was only out for just over a year and a bit before IE6 came out (not forgetting IE5.5 in the middle)

How long is a bit ?

According to Wiki

5.0   Mar 1999

5.5   Jul 2000

6.0   Aug 2001

AndyC said:

W3bbo said:

*snip*

Indeed, I have a sneaking suspicion that IE5 means Quirks mode, because it's probably more understandable that way for the less savvy web developers out there (i.e. the ones who're still writing pages in/for quirks mode)

IE6 was the first version of IE to distinguish standards and quirks mode with the doctype switch. Quirks mode essentially meant "render using IE5's incorrect box model".

IE7 still only had standards vs. quirks mode. It couldn't emulate IE6's standards mode.

IE8 has quirks, IE7 standards, and IE8 standards modes. While it could emulate IE7, apparently they didn't feel the need to emulate IE6 standards mode as well.

IE9 just adds its own new IE9 standards mode, and the ability to emulate IE8 standards mode. It still can't emulate IE6.

As Andy speculated, I agree that "IE5" in the preview simply means quirks mode. IE6 is missing because none of the earlier versions could ever emulate IE6 standards mode.

EDIT: One of the reasons why the real IE's installation is comparatively slow is because most of IE's files are critical OS components that are under Windows File Protection. Replacing those files takes a little more doing than just overwriting them (if you did, WFP would simply put the old version back). The preview doesn't replace anything (since it's installed side-by-side) so it doesn't need to do that and can install much quicker.

Sven Groot said:

AndyC said:

*snip*

IE6 was the first version of IE to distinguish standards and quirks mode with the doctype switch. Quirks mode essentially meant "render using IE5's incorrect box model".

IE7 still only had standards vs. quirks mode. It couldn't emulate IE6's standards mode.

IE8 has quirks, IE7 standards, and IE8 standards modes. While it could emulate IE7, apparently they didn't feel the need to emulate IE6 standards mode as well.

IE9 just adds its own new IE9 standards mode, and the ability to emulate IE8 standards mode. It still can't emulate IE6.

 

As Andy speculated, I agree that "IE5" in the preview simply means quirks mode. IE6 is missing because none of the earlier versions could ever emulate IE6 standards mode.

 

EDIT: One of the reasons why the real IE's installation is comparatively slow is because most of IE's files are critical OS components that are under Windows File Protection. Replacing those files takes a little more doing than just overwriting them (if you did, WFP would simply put the old version back). The preview doesn't replace anything (since it's installed side-by-side) so it doesn't need to do that and can install much quicker.

IE5 mode ~= 'quirks' mode ~= IE6 mode

How confusing.

How about we just label it: f*ked-up mode.