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HTML | What is <marquee> and what can i do with it?

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问题 I just found out that there is a html tag called <marquee> . I went to several websites including the w3schools and the selfHTML website but couldnt find anything about this tag. IntelliJ wich I'm using to write my websites, doesnot recognise this tag. It says: Unkown html tag marquee . This tag is how I tested compatible with all browsers( even in IE! ). So now I have the following Questions: What atributes can I use for this tag? Why isnt this tag on the html-turtorial sites? If its not in

Is it necessary to use lowercase for every Element and attribute , properties in css and xhtml ?

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问题 4.2. Element and attribute names must be in lower case XHTML documents must use lower case for all HTML element and attribute names. This difference is necessary because XML is case-sensitive e.g. <li> and <LI> are different tags. Source : http://www.w3.org/TR/2002/REC-xhtml1-20020801/diffs.html#h-4.2 But is it also necessary for attributes, properties, values, class and ID for elements. Upper case and came case should not be used. What is the benefit of use lowercase for every thing? 回答1:

How to validate CSS3 HSLA color values?

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问题 I like checking CSS validity. It makes things work better. However, a stylesheet I'm using specifies some colors, like so.. border-right: 1px solid hsla( 0, 0%, 0%, 0.2 ); which results in an error when using the W3C validation services (even with level=css3 set), such as... Value Error : border-right Too many values or values are not recognized : 1px solid hsla(0,0%,0%,0.2 ) I also tried... border-left: 1px solid ; border-left-color: hsla( 0, 0%, 100%, 0.3 ); but that returns... Value Error

Why does CORS not seem to work with POST?

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问题 Mozilla's own specification says simple GET or POST should be natively CORS's without preflighting but so far every POST attempt I've made has resulted in an OPTIONS header going out. When I change it from POST to get the code immediately sends a proper GET request so the cross site part is working fine. Here's a slimmed down sample of what I'm doing in firefox: var destinationUrl = 'http://imaginarydevelopment.com/postURL'; var invocation = new XMLHttpRequest(); if (invocation) { invocation

is there any css validator with CSS3 and vendor specific extensions support?

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问题 is there any css validator with CSS3 and vendor specific extensions support? I only want to see problem other than CSS 3 and vendor specific extensions related errors. And is there any better xhtml css validator than W3C's? 回答1: You can select "CSS Level 3" in the More options>Profile section of the W3C CSS Validator. Although this won't help with the vendor-specific errors. It looks like there is no intention to support these in the W3C validator. 回答2: The W3C Validator unfortunately goes

Table Disobeys W3C Box Model, Ie8 Ignores Fixed Table Width !

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问题 I'm having hard time with tables and column widths. Update: I'm using XHTML Strict 1.0. The page is: http://www.pro-turk.net/try The first problem I have is, I have a column with a fixed width of 100px and 4px padding, but it disobeys my padding depending on the value. The column width (as the distance between two borders according to W3C Box Model) is 156 px even if padding is 0 or 4. Only the position of the text changes. According to W3C Box Model ( available at www.pro-turk.net/box_model

Run custom javascript code after loading any website

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问题 I am working on taking readings about web browser performance and so need to access the window.performance object of the browser. To collect this data i have written a javascript file, collect.js which i need to add to the DOM of the page that i need to test eg. www.google.com, www.facebook.com and so on... Also i need to run this test for about 1000 websites, any manual approach is out of the question. I need it to be automated somehow. How could i go about doing this? EDIT: I need to run

IE cannot find the W3C XHTML DTD (Error 2146697204)

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问题 I have a template that starts every page like this: <?xml version="1.0" encoding="utf-8"?>  <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd" > <html xmlns="http://www.w3.org/1999/xhtml"> ... </html> that produces the error: The XML page cannot be displayed Cannot view XML input using style sheet. Please correct the error and then click the Refresh button, or try again later. The server did not understand

Question on CSS Media Query

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问题 I have a question on CSS media query.. I am implementing a HTML page using desktop.css and ipad.css and want them in 2 separate file.. In desktop.css, I use @import url("ipad.css"); and also add @media not only screen and (device-width:768px) block which has the actual desktop styles.. So desktop.css looks like @import url("ipad.css"); @media not only screen and (device-width:768px) { //Desktop styles } Now while the iPad CSS gets applied correctly on the iPad, for some reason the CSS for

Is XML's root closing tag mandatory?

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问题 I serialized an object in Java, and I got the following XML: <?xml version="1.0" encoding="UTF-8"?> <java version="1.8.0_92" class="java.beans.XMLDecoder"> <object class="...." id="SmartLayout0">  </object> As you see, the root tag <java> is not closed. Is it legal in XML to not close this root tag? Does the XML standard explicitly allow such shortcut? 回答1: Yes, unlike in the non-XHTML versions of HTML, all tags in XML must be closed or be self-closing. All elements in XML must be