DevTools/Fission

About

DevTools support for cross-site iframes with Fission is in progress and this page summarizes the current state.

The DevTools team is listening in in the #devtools:mozilla.org room on Mozilla's Matrix server.

Instructions for enabling Fission for DevTools:

1. In about:config, set the "fission.autostart"
2. Restart the browser

You can file DevTools Fission related bug in Bugzilla, here.

See detailed testing results (gdoc)

Fission Compatibility

Fixing known issues is split into two milestones (M2 and M3).

Panels

Summary of known issues related to DevTools panels.

Accessibility

The Accessibility panel is fully compatible with Fission.

Application

• M3 Service Workers coming from remote frames are not displayed (bug 1473257).

Performance

• M2 New Fission compatible Performance panel will be enabled (by default) at the end of October.

Inspector

• M2 Basic support for highlighting elements in the page when inspecting their CSS properties and box model (bug 1623667, bug 1572654)
• M3 Advanced features related to highlighting elements in the page. This includes support for highlighting grid elements, shapes defined using CSS clip-path property, highlighting fonts, geometry editor for absolute positioned elements within relative positioned elements and inspecting CSS animations (bug 1568827)
• M3 Search within the Inspector panel doesn't included remote iframes (bug 1568880)
• M3 Eydropper (a button in the Inspector's panel toolbar ) used to grab a color from the page (bug 1568831)

Console

• M2 Properly show all messages including those coming from frames loaded from different domains (bug 1663706)

Network

• M2 Properly show all HTTP requests including those coming from frames loaded from different domains (bug 1663523, bug 1662736)
• M3 Proper support for the following actions: Block requests, Reload page, Resend an existing request (bug 1667370, bug 1594726, bug 1594728)

Debugger

• M2 Breakpoints should work as expected including those in `onLoad` scripts
• M3 Debugging of service workers should work as expected
• M3 Special breakpoints set for: DOM mutation, XHR, various DOM events, Logpoints and Watchpoints should work as expected.

Style Editor

Compatible with Fission, but there is some remaining work (Bug 1664941).

Storage

• M2 Show all data coming from remote frames: Cookies, Session & Local storage, Extension storage, IndexDB and Cache data (bug 1644192)

Memory

• M3 Memory usage of remote frames is not displayed.

DOM

• M3 Objects coming from remote frames are not displayed.

Miscellaneous Features

Summary of known issues related to independent features.

Screenshot

• M3 Screenshot doesn't work with remote frames (bug 1568833)

Service Workers

• M3 Support for Service Workers is not not compatible with Fission.