1261869 - Firefox ::
Developer Tools: Memory - DevTools are leaking windows (and other
objects) across refreshes, until DevTools are closed
I dug into this, but hit a wall where I couldn't get any useful information on why things were retained. I don't know how to proceed with it, but I consider it high priority since the tool for debugging memory leaks shouldn't be causing leaks and getting in the way of you debugging your own leaks!
Would love some advice on how to proceed here, see comments in the bug for where I got stuck.
1278726 - Firefox :: Developer Tools: Memory - devtools memory panel leaks windows on sites using iframes with postMessage
I suspect this is related to the last one, but I haven't looked into it specifically. Maybe a dupe? Have been putting it off until I figure out the other and was planning on revisiting afterwards to see if it still reproduces.
1278731 - Firefox :: Developer Tools: Memory - devtools memory panel uses a lot of heap-uncategorized memory
I don't think there is any low hanging fruit for reducing the size of deserialized heap snapshots, although there certainly are some things we could try.
I would be up for adding the deserialized heap snapshots to about:memory reporting so that they don't show up as heap-uncategorized. Just need some pointers on what that process looks like (ni'd erahm in the bug).