HTML5 and cellspacing="0" in admin pages

[MattyRob]

There are several instances where generated table content uses 'cellspacing="0"' in the admin areas of WordPress.

The W3C validator (albeit experimental) states that this parameter should be dropped and CSS used instead for HTML5 compliance.

I think the patch I'm going to attach in a moment will fix these validation issues.

[toscho]

padding:0px 0px 0px 0px; should be padding: 0;. Same for other values.

[MattyRob]

@toscho - quite right - can't believe I missed that!

[helenyhou]

Actually, padding is not equivalent to cellspacing. You want border-collapse and border-spacing. If you look carefully, I think you'd find that removing padding like that results in lots of unwanted side effects. Additionally, you'll want to be sure to only apply the rules to table elements with those selectors, as things like .widefat can be used for all kinds of elements. Also, structural CSS should not go in color files but rather the wp-admin.css sheet.

[MattyRob]

@helenyhou,

I had border-collapse and border-spacing in the patch as well as the padding. I'll take your superior knowledge and remove the padding elements and move the CSS to the wp-admin.css file and submit a revised patch later.

The wp-admin.css file contains this:

/* .widefat - main style for tables */

So, does the styling for this need to be applied only to the HTML tag? Is the class being mis-used or is this documentation incorrect?

[MattyRob]

Updated patch with CSS moved into wp-admin.css. I just need to check how the CSS is minified. What service is used for this?

[SergeyBiryukov]

Replying to MattyRob:

I just need to check how the CSS is minified. What service is used for this?

There's no need to patch minified files, a post-commit bot takes care of it.

[MattyRob]

@SergeyBiryukov - thanks, didn't know that.

v4 patch seems to work better - appearance goes off a little with the first patch - top and bottom of tablets gets cropped.

[MattyRob]

Updated against revision 23455

[MattyRob]

Updating against version 25671

[ocean90]

Let's refresh this and get it in.

[azaozz]

The reason for using cellspacing is IE7. It doesn't understand border-spacing. As support for IE7 is on its way out, perhaps can ignore it in this case too.

[nacin]

I'm quite OK with IE7 looking a little off. We currently only care that it is mostly usable and not obviously broken. Pretty is not a goal.

[nacin]

I was looking into IE compatibility of these properties. border-spacing is fine in IE8 as long as it is just one value. It looks like border-collapse: separate is the default, though, so is that needed?

[azaozz]

Yes, border-collapse: separate is not needed. Also there are many more cellspacing than in the patch.

[azaozz]

In 27036:

Remove table cellspacing attribute from the admin, part-props MattyRob, fixes #22086.