Firefox 56 is actually pretty good. It's now fast again. I am using a fresh new profile. Please let me increase "content process count" higher than 7. Chrome o

Firefox 56 is actually pretty good. It's now fast again. I am using a fresh new profile. Please let me increase "content process count" higher than 7. Chrome opens hundreds of child-processes (no problem at all on my PC). And I am still keeping an older Firefox 48 around, as it's the last version that runs Firebug and other good but now unsupported addons. Firebug had this "DOM" panel which showed the non-default DOM attributes in a different color and showed them as first few entries, and the rest below. The DevTools in new Firefox has a less useful DOM panel (it shows all attributes not grouped or colored differently, makes the DOM panel useless and chaotic) - please improve the DOM panel to be feature-equalent to the old Firebug DOM panel!!