embed html in foreign website - html

I would like to know if somebody knows a method to embed custom html in foreign websites.
Maybe there's a firefox extension or something like that (like stylish for example, but for html instead of css)

Actually, that's where the Greasemonkey Add-on is for. Once you have that installed, you can create scripts which manipulate the DOM of any website you would like:
Allows you to customize the way a
webpage displays using small bits of
JavaScript.
Hundreds of scripts, for a wide
variety of popular sites, are already
available at http://userscripts.org.
You can write your own scripts, too.
Check out http://wiki.greasespot.net/
to get started.
Also nice to know is the fact that the latest version of Chrome, and also Opera (don't know since when, but longer than Chrome) supports userscripts out of the box (no need to install any add-ons).

Related

Change look of website

Our office has an email/filing system that is web based (runs on our local servers/intranet) and whilst the functionality is mostly there, it looks like an absolute pig; something that the creators of it appear to have no interest in fixing as it's looked awful for years.
Is there any way I can force the page to load with my own style applied? I use google chrome and have a decent (though not advanced) knowledge of creating web pages.
As far as I can tell, the system doesn't use CSS. I think it's all HTML?
I think you could use JavaScript and CSS to add your own style to the pages on load. Chrome has an extension called Tampermonkey that lets users create userscripts, which are scripts run automatically on pages you specify.
If you create your own style, you can use it on the page with a script like this (this is the jQuery function, I'll try to find out how to do it in plain JS):
$('head').append("<style>//your style</style>");
This should apply the style. If you set the script as a userscript in Tampermonkey, it will run automatically.
Tell me if you would like more details or if I need to be more clear! You can find Tampermonkey at this link on the Chrome store- their website is here.

Is it possible to detect a HTML video playing on a browser?

I want to know if a html video is being displayed on a browser, from outside said browser, ideally without any plugins or such.
Motivation - I am trying to add this feature to Caffeine which is a Linux utility which disables the OS screensaver if, say, you are watching a movie.
The flash support was done I believe by detecting the presence of particular files or folders created by the plugin.
Ideally I would like 1 solution, but if I get 2 solutions for Firefox and Chrome, that's good enough.
p.s. Ultimately this would involve python code, but I am not sure if that is sufficient to make this question on-topic, or if this belongs on Superuser or Unix&Linux
This reminds me of something a web browser I was building in VB .Net which needed to detect if there where web pages that had tags like <a href="tel: or <a href="smsI know you said you didn't want a plugin but I would think you could easily right a browser plugin for for just this. In fact not exactly what your looking for but theirs a script monkey script called Hangouts Unlimited which prevents you from getting annoying messages asking if your still awake while in a G+ hangout. I don't know much about python but I would recomennd trying to identify the elements of the tags and when ever it finds such tags to disable the screen saver. Obviously the hangouts unlimited doesn't affect the web browser and that is most likely why you prefer not to have a browser plugin because you need to access system files outside of the browser. But I hope this helps a bit.

What are Chrome apps vs plugins vs extensions and how to develop them

I am trying to understand about Chrome (browser) development. I am very new to this and trying to figure out where to start in order to develop for Chrome Browser.
Just have a couple of questions:
What is the difference between Chrome Browser apps vs. plugins vs. extensions (not sure, if this question make sense. But, hope you got what I am asking for)
What kind of applications can I develop for Chrome Browser
What technologies do I need to learn in order to develop for Chrome Browser.
To answer your first question this explains the differences between apps and extensions (I think there's no better way to explain their nature):
https://developers.google.com/chrome/web-store/articles/apps_vs_extensions
What do you mean with "what kind of apps"?
You can develop both hosted and packaged apps if is that what you intended, give a look at this:
https://developers.google.com/chrome/apps/docs/index
Anyway the easiest way to start would be by building an extension, how-tos and
good documentation makes it good to start with:
http://developer.chrome.com/extensions/getstarted.html
Just to add to the above answer which was missing difference between Plugin and Extension is:
Plugin is a third-party library that is plugged-in to the browser and allows for being embedded on a webpage. It affects only the web page that is using the plugin.
Extensions change the browser UI, add menus or change overall look of the browser and can process each page that gets loaded.
So to sum it up - plugins add functionality and extra features to a particular webpage while extensions add functionality and features to the whole browser and change the behavior of the browser.
Just to add on new information since people may continue to hit this question: Chrome has basically deprecated plugins as of March 2017 (Chrome 57). If you go to chrome://plugins now, you won't see anything (you used to see a list of installed plugins with enable-disable links like for extensions).
It seems the reasoning is that the only plugins they actually wanted to allow you to enable/disable are Flash and PDF Viewer, both of which were moved to the Settings menus (if they weren't already there, not sure). The rest are considered to be integral parts of the browser. https://www.ghacks.net/2017/01/29/google-removes-plugin-controls-from-chrome/
Makes things a bit simpler to think about now.

How do you use Chrome Extensions to change CSS of a web site?

I'm looking to create an extension for personal and possibly personal friend usage as well that simply changes a few colors that are displayed on a website I visit. I use Reddit Enhancement Suite, which has options for 'Night mode' that completely changes the color appearance of Reddit.
I would like to know how to edit or inject CSS code to this website so that the colors used in the website are what I would like them to be when I view the page. Mind you, this is of course just in my browser or in another Chrome browser using my extension.
You can do exactly as you said: you can inject a CSS file or code into the page.
The easiest way is through the manifest (look at the CSS property).
You only need to complete your manifest.json in order for Chrome to know in which pages it has to insert your CSS file into.
If you want to decide programatically when to insert the CSS, you can use chrome.tabs.insertCSS(), where you can insert a CSS file or just the code as a string.
Instead of an extension, you could also do it in a user script. Then you can simply use GM_addStyle, just like with Greasemonkey scripts. It's much simpler to write and more lightweight in terms of memory usage.
There are already extensions made for this. The one I use is called Stylish, which only modifies appearance using CSS3 only, and not html. There are other extensions as well, do some google searches and you will find a few more.

Modify Google Chrome or Mozilla Firefox display settings

I would like to know if it is possible to modify Chrome or Firefox display settings, so that it would only show rectangles of HTML DOM objects? What I want to do is to decrease rendering engine job amount as much as possible, so it would only build layout of the page.
People usually refer to this mode of operation as "headless" (i.e. without UI).
Usually there's an additional requirement - to be able to run it server-side without the usual for client software installed. If you're running it client-side, I wouldn't bother about optimization, it shouldn't give you a big win anyway.
Otherwise, try searching using that term. I've seen it asked for several times, but haven't seen a working out-of-box solution.
[edit] just saw http://hg.mozilla.org/incubator/offscreen, which seems to be a headless version of Mozilla.
I wouldn't go as low-level as modifying the renderer. Instead, I suggest you use Firefox's Greasemonkey to replace the elements from the page with whatever it is you need. You'll need to know a bit of JavaScript, but it's not that hard.
However, this will only work on client side. If you want to do this on server-side ( so that it will work on any page a user requests through your own ), my guess is you'll need to grab the page's content in a string, and then modify it using a HTML parser.