Firefox Developer Tools ideas

Welcome to the feedback channel for Firefox Developer Tools. This is a place for constructive feedback around the tools with ideas and feature suggestions. It is not a support forum or place to report bugs. For support, please go to the #devtools channel on Mozilla IRC or the firefox-developer-tools tag on Stack Overflow, and for reporting bugs, go to Bugzilla.

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  1. Display :before & :after defined for an element in the DOM tree

    If a DOM element have either a :before or :after pseudo-element with content different than none, a :before/:after entry is displayed in the DOM at their respective position. That entry, once selected, allow to display the styles for it in the properties view.

    186 votes
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      planned  ·  7 comments  ·  Flag idea as inappropriate…  ·  Admin →
    • Support live editing with any external editor

      The architecutre of fb-flo is very nice: http://facebook.github.io/fb-flo/

      It sounds like it needs some deep JavaScript VM foo to do hot code reloading.

      Maybe a Fx Addon for Facebook Flo support?

      Maybe a from scratch way to support any external editor with any codebase?

      22 votes
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        0 comments  ·  Flag idea as inappropriate…  ·  Admin →
      • A JS editor

        Suppose we could edit JS just as we can edit CSS with the CSS editor. So we can change things on the fly and get instant feedback without having to reload the page. Right now the most I can do with regards to JS code is... debug it, which is a bit limiting.

        It'd be awesome if I could edit the code of a function and have it automatically reevaluated and stuff. Not sure if this is even possible at all but hey this is an idea.

        158 votes
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          4 comments  ·  Flag idea as inappropriate…  ·  Admin →
        • Inspect websocket connections

          It will very useful for who works with websockets inspect the traffic and connections.

          116 votes
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            3 comments  ·  Flag idea as inappropriate…  ·  Admin →
          • Make the network panel always active

            Almost every time I open the network panel the first thing I have to do is reload the page I was on because it wasn't active when the requests I care about were made.

            I can understand if there are concerns about memory usage on busy AJAX pages but it seems like at least the level of information present in the Resource Timing API would be enough for the vast majority of tasks I use the network panel to answer.

            95 votes
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              2 comments  ·  Flag idea as inappropriate…  ·  Admin →
            • Make collapsing margins visible and show from which element they come from

              When inspecting HTML elements, CSS margins which collapsed should be highlighted with a new color. It also would be nice if it was possible to show some information about the elements involved and which the margin of which element is visible.

              47 votes
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                0 comments  ·  Flag idea as inappropriate…  ·  Admin →
              • Display JIT information in Debugger and Profiler

                JIT bailouts and invalidation can be expensive, especially in games. Having insights into which parts of your code could not be jitted and why can help to optimize hot loops.

                Showing marks in the Profiler when JIT invalidation happens can give valuable insights for otherwise unexplainable janking.

                11 votes
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                  0 comments  ·  Flag idea as inappropriate…  ·  Admin →
                • 49 votes
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                    planned  ·  0 comments  ·  Flag idea as inappropriate…  ·  Admin →
                  • Grey out non-applied fonts

                    Consider this example CSS rule:

                    body, td, th, input, select, option, optgroup, .text_input {
                    font-family: "Open Sans","Helvetica Neue",Arial,Helvetica,sans-serif;
                    }

                    Only one of these fonts is going to be applied on the page, depending on what is available on the system.

                    It would be nice if the devtools' Rules view would grey out all the fonts that are not actually applied, so as to let the user know which one got applied in the end.

                    related bug: https://bugzilla.mozilla.org/show_bug.cgi?id=994559

                    65 votes
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                      planned  ·  0 comments  ·  Flag idea as inappropriate…  ·  Admin →
                    • Positioning information in Box Model view

                      I've been finding myself wishing the box model view showed positioning information. Specifically, I'd like to see the following attributes:

                      * display
                      * position
                      * top, right, bottom, left
                      * z-index

                      5 votes
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                        2 comments  ·  Flag idea as inappropriate…  ·  Admin →
                      • Device Orientation emulation with the Firefox OS simulator in App Manager

                        Adding a feature to emulate the accelerometer in the Firefox OS simulator. It will never replace a real device, but will be helpful for testing purpose with:
                        - how much the device has been rotated around the z-axis.
                        - how much the device is tilted left-to-right.
                        - how much it's tilted front-to-back.

                        13 votes
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                          1 comment  ·  Flag idea as inappropriate…  ·  Admin →
                        • Geolocation emulation with the Firefox OS simulator in App Manager

                          Can we add an option to fake the GPS, so developers can test their applications using geolocation.

                          It was previously in the simulator, but was removed, I think, when we went from the Firefox OS Simulator 4.x to App Manager. Can we add it back in the simulators used in App Manager? It was useful for developers using the geolocation in their application.

                          24 votes
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                            2 comments  ·  Flag idea as inappropriate…  ·  Admin →
                          • Keep the dotted outline when an element is clicked with the Inspector

                            Before Firefox 29, when we clicked on an element with the inspector tool, the dotted outline stay visible.
                            It allowed us to see the effect of the newly applied CSS rules on the element position.

                            Since Firefox 29, the dotted outline fade out once the element is clicked.

                            I'd like to see an option to keep this dotted outline visible.

                            18 votes
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                              1 comment  ·  Flag idea as inappropriate…  ·  Admin →
                            • Show compressed and uncompressed size of http responses in network tab

                              The Size column in the list of http requests in the network tab only shows a number. It would be useful to know if this is the compressed size, how.much the uncompressed is, a percentage, etc

                              16 votes
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                                planned  ·  1 comment  ·  Flag idea as inappropriate…  ·  Admin →
                              • firebug-like DOM panel

                                Please include a DOM panel like the one in Firebug, but especially the ability to see and modify local and session storage.

                                5 votes
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                                  0 comments  ·  Flag idea as inappropriate…  ·  Admin →
                                • Property grouping

                                  Computed properties in the inspector's computed-view are sorted alphabetically. It could help grouping them by types instead.

                                  Firebug groups them by Text, Background, Box-Model, Layout, ...
                                  I'm not saying we should do exactly the same, but I think this grouping helps (+ the group headers have collapse/expand arrows and the state remains when new nodes are selected, which helps if you're only interested in one set of properties).

                                  related bug: https://bugzilla.mozilla.org/show_bug.cgi?id=977128

                                  3 votes
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                                    planned  ·  0 comments  ·  Flag idea as inappropriate…  ·  Admin →
                                  • Get rid of sub-windows when clicking on a Network item in the Console tab.

                                    Why does the network request & response data open in a sub-window? This is clunky when the contents of the window are important enough to be in the sidebar, like how logged objects are clickable.

                                    10 votes
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                                      2 comments  ·  Flag idea as inappropriate…  ·  Admin →
                                    • add an option to show the browser rules in the "rules" sub panel

                                      Currently, we can toggle the browser rules in the "computed" sub panel, but not in the "rules" sub panel. This would be super useful to have them here as well.

                                      Note that Firebug has this option ("show the default rules").

                                      related bug: https://bugzilla.mozilla.org/show_bug.cgi?id=940950

                                      3 votes
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                                        planned  ·  0 comments  ·  Flag idea as inappropriate…  ·  Admin →
                                      • Add "Open Link In New Tab" item to stylesheet list

                                        When I'm opening a page sometimes I want to get ahold of the original URL for the style sheets I'm looking at. When I right click on a stylesheet in the style editor, there should be an option to open it in a new link right next to the 'show original sources' option.

                                        I'd also like this in the style inspector - we can handle this in a different bug, but I know getting this original URL should be shared functionality since it is done in a couple of places.

                                        related bug: https://bugzilla.mozilla.org/show_bug.cgi?id=992947

                                        18 votes
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                                          planned  ·  0 comments  ·  Flag idea as inappropriate…  ·  Admin →
                                        • Add a DOM View to the inspector

                                          Allow an easy way to view the DOM for a node with a DOM button. The new sidebar would display the same information currently shown by: inspect($0)

                                          related bug: https://bugzilla.mozilla.org/show_bug.cgi?id=704094

                                          6 votes
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                                            planned  ·  0 comments  ·  Flag idea as inappropriate…  ·  Admin →
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