Can you edit javascript firebug

On a production machine, we're seeing a very weird bug that we have not been able to understand. We have never been able to replicate it in a local or development environment. It might be related to the javascript, but I haven't found a good way to do this: use my browser to visit the page on the production website and then use browser tools to edit the javascript that runs on that page, including on reloads of the page.

I'm always able to do this to tweak CSS etc, but as these questions point out, it's not obvious how to tweak JS client-side:. It seems like How to modify javascript code on the fly in browser in debugging mode? JavaScript can modify the DOM, send Ajax requests, and dynamically modify existing objects and functions at runtime. So, once you have loaded a page with JavaScript, it might be completely different after the JavaScript has run.

The browser would have to keep track of every modification your JavaScript code performs so that when you edit the JS, it rolls back the changes to a clean page. The first two options are great because you can modify any JavaScript variables and functions currently in scope. However, you won't be able to modify the code and run it with a "just-served" page, like you can with the third option.

Other than that, as far as I know, there is no edit-and-run JavaScript editor in the browser. Hope this helps,. Login using GitHub Register. Ask a Question. I'm always able to do this to tweak CSS etc, but as these questions point out, it's not obvious how to tweak JS client-side: Best way to capture JavaScript errors in production?

How do you edit Javascript in the browser? Max Kielland Max Kielland 5, 7 7 gold badges 51 51 silver badges 89 89 bronze badges. Note that in the latest version of Firefox you have to enable this option first. At the right top of the toolbar press the config wheel icon "Toolbar Options" and check under the header "Default Firefox Developer Tools" the checkbox "Scratchpad".

Sebastian Zartner Pavle Lekic Pavle Lekic 1 1 gold badge 12 12 silver badges 28 28 bronze badges. You can't do it. You should use javascript console to redefine functions.

Pavel Strakhov Pavel Strakhov Shawn Chin LearningEveryday LearningEveryday 1 1 gold badge 3 3 silver badges 12 12 bronze badges. Fiddler seem a good idea. It's an external application that intercepts the web requests so that you can make live-edits of the JS etc. Sign up or log in Sign up using Google. Sign up using Facebook. Sign up using Email and Password. Post as a guest Name. Email Required, but never shown. The Overflow Blog.

Does ES6 make JavaScript frameworks obsolete? Podcast Do polyglots have an edge when it comes to mastering programming Featured on Meta. Now live: A fully responsive profile. How to edit JavaScript in Firebug? Asked 4 Months ago Answers: 5 Viewed 25 times. Original answer: Check for the console object created only with Firebug , like such: if window. You can still detect the presence of Firebug by duck typing like if window. Make use of Firebug for this check the below link will give you more info.

RegisterClientScriptBlock this, this. GetType , "myScriptName", myScriptValue, true ; Copy all of javascript into string and then register it into your aspx page in code-behind. Only authorized users can answer the question. Please sign in first, or register a free account.