How can I activate the Firefox debugger? - firefox-addon

While debugging a JavaScript program I was writing with Firebug, the Script panel stopped working and I got the following message:
I went through all menus and sub-menus I could find but didn't see a option to re-enable this feature. The console.log() command doesn't work in Firebug as well (while it does work in the built-in devtools' console).
How can I re-activate the Firebug Script panel? What may have caused this?

This may have different causes. One of them is described in issue 5646, which is related to going back and forward in the browser history.
In such cases it normally requires a browser restart to work again.
Note that Firebug up to version 1.12 is based on an old debugger API exposed by Firefox called JSD, which is unmaintained and buggy. Since version 2.0 Firebug uses a new debugger API, which fixes this problem.

Coincidentally, I just "fixed" the same problem with my Firebug.
I went through re-installs, options resets and such and nothing helped.
After some investigation it boiled down to the content of the page I was debugging.
I have a function called by jQuery when page load is finished:
<script>
$(onPageLoad);
</script>
Now, this function asks user to enter his name using prompt() function. It appeared that Firebug wouldn't activate script panel until prompt() is closed. That is not a problem when you have just one page opened since you just close the dialog and everything works. However, it is a problem when you have two same pages opened. Script panel is non-operational until you close both prompts.

I was facing this problem recently. I found that my Firebug was not getting updated because my Firefox was stuck on 29.x. Once I updated my Firefox the new Firebug got installed. It supports only Firefox 30+.
Note: I was using OSX v1.9.3.

I was having same problem, and, thanks to Roman Guralink, I figured out that the the dialogue Firefox prompts you to insert the master password was the cause. When you set a master password for all password stored, FFox usually opens a dialogue to ask it just after program started. BUT, sometimes this dialogu goes behind the main window, and you don't notice it is there.

Related

How to troubleshoot application page hung issues in Internet Explorer 11 in Windows 7

we have a Struts 2 application. It has a web page that works fine in all browsers except IE 11. The page hangs while loading and stops responding. How to troubleshoot the page hung issues in IE 11 ? Please give some tips.
You could use a virtual machine to achieve so. Refer to Microsoft virtual machines download page for more information. The only problem is that you will be able to test IE8 as the minimum version. There is a specific VM with Windows 7 and Internet Explorer, so if you can use a VM you will be able to test your app.
Other possible solution is to use IETester, it has some bugs, but you can even download a debug bar for it.
Hope it helps.
Finally, we were able to resolve the hung issue in IE browser. We did the following :
In IE, we opened the F12 Developer Tools and went to the Debugger tab.
Clicked on the page that was getting hung.
In the Debugger tab, it showed the line number that was resulting in error. The error was something like "method not supported". The code was
document.form.submit="post".
Made changes in code to solve the error. I modified tag with property method="post" instead of "get".
This fixed the issue.

Firefox JavaScript debugger: wrong cookie value sent

I'm running Firefox 36.0.4 on Windows 7 32-bit. I've diabled all add-ons, extensions and user scripts before retesting this.
I'd like to step through JavaScript code that is served up in a <script> tag in the HTML document being produced by a Java (Tomcat) web server.
Unfortunately, when I select the HTML document under Debugger > Sources, the source of the page returns to the login page of the application - it appears that session information is not being used to request the source.
I stepped through the server-side code and found that the correct session cookie values were being sent for the real page request and some AJAX requests sent by the page. However, when I tried to load the page source in the JavaScript debugger, I found that an incorrect session cookie was being sent by the JavaScript debugger.
I can replicate this behaviour in other webapps, not just my own. For example, Stack Overflow:
Is this a configuration issue, or a bug in the Firefox Developer Tools?
I can't reproduce your problem using StackOverflow as an example, at least in Firefox Developer Edition ( currently version 38 ):
One thing that might help - try disabling the cache while the toolbox is open - this setting is in the developer tools setting panel ( click on the 'gear' icon at the top right of the toolbox ):
After reviewing canuckistani's answer, I downloaded Firefox Developer Edition. Seemingly, the problem was fixed.
Five minutes in, I became sick of being asked whether to remember passwords and having to manually clear session cookies (I prefer being able to do it by simply closing the browser) - it makes testing easier.
As per usual, I went to Options > Privacy > History to disable this behaviour, by setting the value to Never remember history.
Changing this setting requires the browser to restart. However, upon restarting, I once again saw the same erroneous behaviour - the wrong session cookie was being sent to the web application again.
The workaround here is to not use the Never remember history setting. I have filed a bug report at Mozilla.org Bugzilla.

Debugging javascript with Plunker

I am just starting out with Plunker, and I want to use Firefox or Chrome developer tools to debug javascript. It looks like the javascript files get cached the first time I open them in the debugger panel. How can I get the panel to refresh after I make changes to the javascript? (I've tried developer tools in Chrome and Firefox, and I've tried Firebug too)
in chrome:
open the developer tools
open the file you want to debug: Ctrl+O and type app.js or similar
set a breakpoint
the only tricky part is the 2nd step, since the file is in a very obscure location, fortunately Ctrl+O comes handy

Uploadify not clickable in JQuery UI's Dialog and Firefox 17

This is a really weird issue. I've first read the answer from Maayan Glikser on this question which looked similar : Uploadify inside Jquery UI Dialog => Chrome & Opera bugs
It didn't work at all. Let me explain my problem.
I have 3 different Uplodify (Flash version) controls on my website (not on the same pages), only one of them doesn't work and it's the one that is inside a JQuery UI Dialog. Basically, the button is visible but not clickable. The problem occurs only for this particular control, the others behave normally.
So I tried adjusting the z-index inside the javascript, it didn't change anything. Then I tried adding manually (through firebug's "edit html" feature) a <br /> at the beginning of the container generated by uploadify and bam, the button became clickable
I then tried adding the <br /> on page load with $("#fmuploader").prepend('<br />') and nothing happened, the line break was added but the button wasn't clickable. When I added manually a blank space it became clickable again.
I believe there is some kind of paint event that gets triggered when you manually edit the page from firebug which makes the button suddenly become clickable, but I'm really wondering if I can make it finally work as intended without asking all my firefox-using visitors to install firebug :)
It is really hard to explain so I have setup a small test page at this address : deleted (edit: the test page is now offline on the production environment and is no longer reachable)
This reproduces exactly the problem I have.
Load the page, click the link to open the popup, open firebug, find the uploader's container <div id="fmuploader" class="uploadify" style="height: 30px; width: 120px;"> and just add a blank space after the opening tag. The button becomes clickable.
The problem occurs on Firefox 17 with no add-ons except firebug and Flash 11. The problem does not occur on IE 7/8/9 and Chrome on the same machine.
Update: I tested it with Firefox 15 and wasn't able to reproduce the bug.
I had a similar issue, but found that updating Firebug to version 1.11 sorted it.
It was only seemed to be the issue in verstion 1.10.
Looks like a change in the Firefox 17 security model means that minified version of jQuery breaks when using Firebug. Plenty of jQuery based stuff has stopped working for me in Firefox 17 unless I disable Firebug.
https://blog.mozilla.org/addons/2012/08/20/exposing-objects-to-content-safely/
https://developer.mozilla.org/en-US/docs/XPConnect_wrappers

Firebug lite on iPad

Already found this page with some helpful hints.
Problem is I need to debug a web application on a CMS using an iPad and Safari.
So far I haven't been able to make firebug-lite work. I am working in a secured environment having no internet acces, but can copy files using a USB-key.
I have copied firebug-lite.js to the local server and included the file in a script tag in the head:
<script type="text/javascript" src="http://my_server/js/firebug-lite.js"></script>
Unfortunatly when I open the page in the CMS I cannot see the firebug-lite-button on the page. Verifying the source code firebug-lite should have been loaded on the page. There is no way to get a right click menu to inspect anything.
What can I do to make firebug-lite work on the iPad? What am I doing wrong?
Start Firebug Lite already opened, as per http://getfirebug.com/firebuglite#Options :
<script type="text/javascript" src="proto://path/to/firebug-lite.js#startOpened=true"></script>
I think you won't be able to inspect elements, but you can navigate to the elements in the DOM tree provided by Firebug Lite.
It looks like Firebug-lite has problems with the iPad browser since late 2010.
The problem (ticket on official tracker) has not been yet solved.
Have you tested the problematic page in Safari/Chrome/Chromium for desktop? Since they use Webkit, the same system used with mobile Safari/Chrome, you may be able to duplicate the error and find its solution. You can open Chrome's debugger with right click, Inspect element.

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