Develop Reference

JavaScript alert with image and link

I was navigating on this page and clicked "Available for your computer" image.
Then a native browser popup that is like an alert was opened:
Please compare the one above with the following alert() that everybody knows:
How did they create such an alert?
alert seems not to support images, according to this question.
Is this possible to open with JavaScript? I guess yes, but how?
Is this cross-browser? On Firefox, I am redirected to Chrome download page.
NOTE: I DO know that there are a lot of JavaScript libraries to show alerts, but I DO NOT want to use any of them. I want a clear answer to my question.

Chrome has some specialized windows/popups available for it's own use .. things you can't do via regular JavaScript.
Other things you can't do via regular JavaScript are the
Enable Webcam prompt window
Download file window.
If you are trying to do something similar in pure JavaScript, this is a great little replacement:
http://www.codersgrid.com/2013/07/05/alertify-js-replacement-of-your-browser-alert-dialog/

This seems to be a "chrome specific" popup. The application you want to install by clicking on this button is a Google App, which install is handled by Chrome. I think.
Except Bootstrap-like modals, I have never seen such thing in Javascript before.
Check this if you want to implement such popups on your website:
http://getbootstrap.com/javascript/#modals

instead of using alert . you can use any external plugin confirm box.Then you can customize your dialog box

Is it possible to inject HTML into a website to force-enable scrolling?

Okay, so this is a bit of an odd question. Facebook is trying to remove the feature that hides your profile from search, but requires you hit an accept button before they can remove it. I like my privacy, so instead I just used ABP to hide the dialog box and give me back access to the page. The problem is that scrolling has been disabled, so while I can interact with the content that's currently visible, I can't scroll down. Is there a way to inject HTML or JS that would force-enable scrolling?

Seems as a job for greasemonkey
https://addons.mozilla.org/sv-se/firefox/addon/greasemonkey/
There are similar plugins for other browsers, Chrome have support for users scripts by default but there is a great addon there as well
https://chrome.google.com/webstore/detail/tampermonkey/dhdgffkkebhmkfjojejmpbldmpobfkfo
Internet Explorer can also offer this by adding Trixie
http://trixie.softpedia.com/

If you don't need it all the time and don't want to go to the effort of making a script you could just edit the html directly using either the developer tools built in to most browsers and inspecting the element.
Just right click what you want to change and select inspect element.
Adam

How to know if something is programmed in Flash or Javascript

I was looking for examples of Javascript games and I came across this. It looks like Flash. I tried looking at the source code, and all I see are a bunch of div tags, but not really any Javascript. I couldn't find the code that actually runs the game.
Is this Flash or Javascript? How can you tell?

It's Javascript.
When you right click it gives you the native browser context menu. Right-clicking anything in Flash will give you a Flash context menu. The only time that method fails is when you get no context menu at all.
Also, highlight the text "Press enter". It uses native text highlighting.

As far as I know is impossible to hide the typical secondary flash context menu telling the version, etc...
I found is using a core.js javascript
Hope it helps.

You can try to disable the plugin of shockwave flash from browser's options. Then refresh page and see, whether 'target flash' disappears. If so then it was flash.

Creating new tab / switching between Tabs in Firefox?

I am looking for a way to improve the workflow in a PHP based CMS. There is a lot of switching between the editor mode and the preview mode of the page. The editor mode is huge to load, and so I would like to open the preview mode in a different window.
I don't want to use new windows or an iframe within the current window to keep the workflow simple and to avoid confusion.
Is there a way to explicitly open a new tab (not window), and to jump to that tab from a document, in Firefox? The number of users is limited, so there is the possibility to set up the client with the necessary extensions / permissions.
I know Firefox can be forced to open all links in tabs, but I think that won't cut it, as I still can't address and focus the newly opened window.
Thanks for all the great answers everyone. I have now enough material to decide whether I'll take the greasemonkey approach, rely on the user to set up "open in tabs" and address the window by name, or use a "inline" HTML solution as so many of you suggested. I am accepting the answer that I feel went most effort into.

There is no way to force a window to open as a tab. It's all dependent on the user's preference settings.

I second the answers that say you should do this in HTML using Javascript. Then it can work in all browsers that support JS.
I would put two divs on the page and show/hide each div depending on which tab is selected. If you are clever about this you could trap the click on the tab and determine if the user left-clicked or middle-clicked. If they left click you load that tab on the page. If they middle-click you let the browser open a new tab/window (according to the user's prefs, don't try to force it), and leave the current window unchanged (that is, don't switch to the new tab). The action for clicking on the tab would be to use AJAX to load the contents of the remote document and put it into the tab. Use Javascript to modify the URL before submitting the AJAX request so that the server knows to send a web page fragment instead of the whole page.
The advantage of this dual-natured solution is that the tabbed approach will work the way you want it to work for the majority of cases, but for users with, say, two screens, or who prefer switching between browser tabs, they will still have the flexibility to work in multi-window mode. This can all be done without any browser extensions and it should work equally well in IE as well as Firefox, Opera, etc. Avoid locking yourself into one browser, even one as excellent as Firefox. One day a customer will need to use Opera or Safari and you'll be stuck.

You say you don't want to use an iframe to avoid confusion. Now I don't know about the layout of your website, but I've been using the approach that the editor opens in its own div right next to the content being edited and the content is being live updated as you edit. No need to change tabs.
(If the window is too narrow there are HTML tabs Edit and Preview)
It does not seem to add confusion to the user and for me this approach works really well. Maybe it's worth considering in your case.

What about using iframes and JavaScript?
I know you said you want to avoid 'confusion using iframes', but in my opinion if you really need to load different pages at the same time this is the best option.
In theory, you could create your own tab system using javascript or even better, using jQuery, because its UI module offers pretty cool tab control.
For every tab you could load separate "headerless-footerless" version of your specific admin page inside <iframe> element. If user wanted to modify something different, he will simply click on the tab and bring different iframe.
All this could also be done using AJAX, but iframe solution is quite easy as you just need to load ready page and all postbacks are already handled by original page and separated from master-admin-page.
You might also need to play a little bit to set correct height of your iframe to fit all the content without scrollbars, but this again, is just bit of javascript.

Nope, there's no way to force the opening of a new tab, simply because this would be unsupported by un-tabbed browsing
You can only set it to open a new window, not a new tab.

Greasemonkey springs to mind - a quick google gives open in tabs on left click. I think you could modify that so it only runs on one particular page, and you'd be up up and away.

This question made me wonder if HTML 5 allows that sort of specification, and it doesn't (nothing in one of the other hyperlink attributes, either). A new browsing context is a new browsing context, there's no way to express a preference for tab over window or foreground over background.

You can't force a tab, but if you use a target with a specific name, like target="my_cms_window", many browsers will open this as a new tab. Additionally, they will remember the name and if you use the target repeatedly, put the contents in the same tab. I have found that this works pretty well in the real world.

modeless window to behave like a modal window using javascript

I have a requirement to have some modal popups appear on a webpage. At first i implemented them as true modal windows, but then i found out that true modal windows cannot communicate with parent window in IE.
Now i am trying to implement them as regular windows that always steal focus, which is sorta working.
Here is the code that i am using:
modalPopup = window.open(url, 'popup', arr.join(",")); //use a global var here
modalPopup.focus();
$(window).bind("focus.modal", function(){
if(modalPopup){
modalPopup.focus();
} else {
$(window).unbind("focus.modal");
}
});
There are several things wrong with this:
In firefox, once i close the popup, the modalPopup does not become null, it points to parent window. (this is ok, since we dont support firefox anyway)
In IE, it works like a charm when you open 1 window and close it, but opening any more windows results in the exception:
Error: The callee (server [not server application]) is not available and disappeared; all connections are invalid. The call did not execute.
edit: In IE the error happens when modalPopup.focus(); is called. apparently modalPopup is never set to a falsy value when closed :P
Can you help me write a better implementation that uses window.open for creating the popups?
Before anyone says anything, using lightbox is not an option. The popup windows contain A TON of html, javascript etc, and loading them in the DOM is not going to result in a good UX. Also, we sorta have to have this work on IE6.

The windows containing a "ton" of JavaScript, HTML, etc. isn't a reason that you can't use "lightbox" style techniques (which do work on IE6; I don't know if a specific library you've looked at doesn't). The technique is simple:
Have an absolutely-positioned iframe on the page whose z-index is higher than any other content normally shown on the page. Normally the iframe is hidden.
When doing a "modal," show that iframe and set it to cover all other content. Create an absolutely-positioned div with a higher z-index than the iframe and place it wherever you want (typically in the middle of the viewport).
Put your "modal" content in that div. This can be pre-loaded, or you can demand-load JavaScript and other resources to fill it.
Have a UI control of some sort on the div that "closes" it by removing the div and hiding the iframe.
You can build very rich UIs with this that (can) have a dramatically better UX than enforced multiple windows. And you have the advantage of avoiding cross-windows communication and potentially offering much better response time to the user when they "open" one of these windows.