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View all created JS objects in chrome

How do I view all JS objects that I created in chrome? I know if I type window into the console, I will see everything, but where is the tab that is filled with all my things?

I think you might be looking for something like Chrome Breakpoints. Basically, in the developer tools, you will go to 'sources', click the file you are wanting to debug, and set a breakpoint on the line in the file that you want to see your active variables. You do this by simply clicking on the line number. When you reload, the browser will pause execution on this line and you will be able to see all the information you are looking for.

How can I find out which methods are called in Javascript when debugging without knowing the methods beforehand?

For example, I want to debug a third party library. It has a plethora of functions within it and I have no idea where to start. Is there a quick way to find out which functions are being fired without prior knowledge of the code base and thus not knowing where to put the break points?

To see which functions are called, you should use the JavaScript profiler of your favorite debugging tool.
Those profilers output information about what functions were called from where and how often (i.e. how costly they are).
In Firebug (version 2.0):
Enable the Script and the Console panel
Switch to the Console panel
Click the Profile button
Do some actions, which call functions within the third-party code.
Click the Profile button again
Result:
In Firefox DevTools:
Switch to the Performance panel
Click the Start Recording Performance button
Do some actions, which call functions within the third-party code.
Click the Stop Recording Performance button
Switch to the Call Tree tab
Result:
In Chrome/Opera DevTools:
Switch to the Timeline panel
Click the Record button (or press Ctrl+E
Do some actions, which call functions within the third-party code.
Click the Finish button
Switch to the Aggregated details tab

Usually third parties have a variable or function they expose, for example jQuery, $ or window.whatever.
The browser developer tools (doesn't matter whether that are the Firefox DevTools, Chrome DevTools, Web Inspector in Opera or Firebug) offer a way to create watch expressions within their JavaScript debugging tools. Depending on the tool you use the related panel is called Watch Expressions, Watch or Variables.
In there, add the variable you DO know, expand it and start your search from there.

How to break on currently running JavaScript

I've a HTML page which contains some hacked script which contains something like, e.g.
setTimeout(function () {
window.location = window.location;
}, 3000);
But assume this page used a lot of minified JS and span over multiple files, with Chrome/Firefox developer tool, how to spot the above section of code from multiple files? i.e. stop the execution and break on the currently running line?

"spot(ting) the above section of code" and "stop(ping) the execution and break on the currently running line" are completely different things.
spot(ting) the above section of code
To find code anywhere in the various source files, your can use Chrome's Dev Tools' global search feature:
Open Dev Tools (F12, Ctrl+Shift+I, or via the menu)
Switch to the Sources pane
Press Ctrl+Shift+F (probably Cmd+Shift+F on a Mac)
Type what you want to find
stop(ping) the execution and break on the currently running line
Open Dev Tools (F12, Ctrl+Shift+I, or via the menu)
Switch to the Sources pane
Click the pause button (it looks like two vertical bars)
Dev Tools should break on the next bit of JavaScript that tries to run (according to this page on developer.chrome.com).

If the code is large and unknown to you, one option is to use the Profiler.
There's a "Profiles" tab in Chrome devtools and a "Performance" tab in Firefox devtools.
Each of these tools behave pretty much the same in that you start a recording, then wait (or perform any action on the page that you know leads to script running), then stop the recording.
The panel in the middle is going to display a call tree of all the scripts that ran during that period of time with columns that should, hopefully, tell you more about what took time.
Using that call tree, you can then drill down to discover what got executed exactly and then from there, jump to the actual line in the script.
Here's the chrome devtools profiler documentation page and here's the firefox devtools counterpart.
One other option you have, using the firefox devtools is the tracer. A tracer is a tool that record everything that occurred at the javascript level: what functions got called, what arguments where passed, what value got returned, what functions did those, in turn, called, ...
To check it out:
open about:config in firefox, then switch pref "devtools.debugger.tracer" to true.
Then open the devtools and switch to the debugger panel.
Then click on the double arrow icon, next to the pause/step over/step in/ step out buttons.
This will start the tracing and switch the side bar to the "traces" panel.
Click again to end the recording.
You should see the trace of what got executed. If you click on any entry in the trace, you'll see the associated script and in the sidebar, the arguments and return values.

How do I find out what functions are called when a button is pressed in Chrome Console?

I am trying to teach myself the Google Closure javascript library. I am examining the TreeControl UI widget.
How can I use Chrome Console to analyze what functions are run when I click on the "Cut" button in the demo below? For instance, can I somehow set a break point for that? I've tried viewing the source and looking around, but I feel that Chrome Console may offer a more systematic method.
https://github.com/google/closure-library/blob/master/closure/goog/demos/tree/demo.html

You may be looking for the "Event Listener Breakpoints" section on the right side of the Debugger area. Open that up and select the click event under "mouse". See the screen image. Then click on the button in the app and you will immediately be taken to the code being executed.

With the Chrome Developer Tools window open, click on the "Sources" tab. If you don't see anything you may need to click on the "Show Navigator" button in the upper-left corner of that tab. With the navigator open, navigate to the file where the cut() function is defined (in your case it's demo.html). When you bring the file into view, find the line where the cut() function is defined and then set a breakpoint on the first line within that function. You can set a breakpoint by clicking the line number on the left side.
Once you've set your breakpoint(s), do something on the page that would trigger the cut() function and the browser should break script execution as soon as it enters the cut() function (assuming your breakpoint is on the first line within the cut() function). From this point you can use the controls on the top right of the tab to step in/out/around code and see what's going on.
Here's a screenshot of me doing it: http://d.pr/i/f6BO
Also, here's a great video that talks about using the Chrome Dev tools, including setting breakpoints: http://www.youtube.com/watch?v=nOEw9iiopwI

The thing that you are looking for is called 'Profiling'.
It can be achieved by:
Go to Profiles
Choose first option ('Collect JavaScript CPU Profile')
Start it before pressing button 'Cut'

This may be helpful for some people:
You can right click an element on the elements tab and use 'break on' to break on e.g. sub element modification. https://developer.chrome.com/devtools/docs/javascript-debugging

How do I identify if I have a javascript conflict on my website?

I'm currently moving a website from self hosted onto a CMS system. The current site uses a modal popup script called SqueezeBox.js
I've copied the code across exactly how it looks on the current website, however the modal popup box isn't triggering when I click on a thumbnail image.
Looking at the code in the header I've spotted that the CMS I'm using is also calling a number of other javascript files and I'm wondering if one of them is causing a conflict.
What's the best way to find out if this is the case? I've tried Firefox's plugin Web Developer but can't see anything in the Error Console. However I'm not 100% sure I'm using it correctly. Can anyone else point me in the direction of a simple to use javascript conflict detector?
Cheers
Adam

If you have Google Chrome, open up the Developer Tools and you can go into the 'scripts' tab, open up your javascript files and look for the click handler.. click along the side of the code to set a breakpoint, then when the code reaches that spot (if you click it, for example), it will pause, and then in the Developer Tools you can see what functions are being called where as you step through the code. You can also hover over any variable in the code window to see its value. Very handy! You can then see if it's getting into your plugin at all (you can do this as well by setting a breakpoint inside the plugin at a place like the first line that will always be accessed when its run).
I believe you can do the same thing with Firebug
It's a bit of a different thinking process to get into (step into, step over, turning breakpoints on and off etc) but it's extremely useful.
A more simple way of checking where problems are occuring is by adding an alert('im working); or something similar to code you're not sure if it's working. You can also alert a variable to see what the value is at that point. You can also use console command to print it to firebug's console. These are doing things that breakpoints/debugging do for you except with the debugging you don't need to change your code.

If there is a javascript error, then the easies way is using firebug or the Chrome Inspector (right click on the thumbnail and choose "Inspect element"). Open the console tab of either and refresh the page. If there is an error, it will be reported in the console and provide a link to the relevant line.
If there is no error being reported, then the code's logic is preventing the box from being displayed. You'll need to step through the code to find the error. Look at what function is being called from the click handler of the thumbnail image. Go to that function in either tool and place a breakpoint on the first line of the function. Click the thumbnail again and the code will pause on that line. From there you can step through the code and see which code branch is followed. There's likely a sanity check at some point that fails and causes the code to bomb out.