The DevTools team is primarily focused on adopting our entire code base to Fission these days (to deal with many more processes on a web page) and so we are not shipping as many new features as usual.
But, some nice improvements and ONE fresh new side panel made it to Firefox 77 so, make sure to scan this email till the end :-)
You might also use this query to see all of the DevTools bugs fixed in April 2020.
Network panel indicating lazy loaded resources (bug). There is a new lazy-img flag in the Cause column that is used for all lazy loaded resources.
WebSocket Inspector allows hiding control frames (bug). The existing drop-down filter has an additional optional item that can be used to hide WS control frames.
New Network Settings drop down menu available in the toolbar (bug). The existing Persist Log option and HAR actions were moved into the menu.
Watchpoint supports pausing on either get or set (bug). Now you can pause JS execution when a property is either accessed or modified.
New Context Menu for list of blocking rules in the Blocking Panel (bug).
Stepping in the debugger now uses the selected frame as a reference point (bug). This is one of the small improvements that nicely improves debugging workflow. Imaging the following scenario:
Pause in Debugger on line 12 (see the screenshot below)
Select one of the parent frames (onTest, line 2)
Step Over to go to line 3 in the selected frame. Previously you would end up on the next execution line in the current frame (i.e. line 13)
This feature allows you to nicely jump into any of the parent frames quickly.
New Debugger Settings drop down menu available in the toolbar (bug). It’s easier and faster to use options from this menu as opposed to going to the Settings panel (didn’t you know a Settings panel exist? Just press F1 while being in the DevTools Toolbox :-)
New Compatibility Panel enabled in Nightly and DevEdition (bug). The panel is showing CSS compatibility issues based on data from MDN. Note the feedback button available in the panel's footer that is used to collect user feedback It points to a feedback form.