I really like the built-in Task Manager in Chromium based browsers (Chrome/Edge/Vivaldi):
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In Firefox, we have about:performance but it has some shortcomings:
- Not easily discoverable (Chromium has a keyboard shortcut and a menu item)
- Columns do not sort continuously
- FF uses Energy Impact while Chromium shows CPU (although this may not be a big deal)
- Chromium includes Network column 😍
Would love to see this kind of functionality in Firefox!