4 ms·

IIRC Mozilla said recently (last week or two) that they had managed to patch the bug responsible for the majority of battery issues on macOS.

• kalleboo 7y ago
  Tests showed this finally brought power usage inline with Chrome, but not down to Safari levels.
• submeta 7y ago
  I can confirm: Been using Firefox for months on my Mac, and it is not draining my battery like it did a few years ago. It used to be very resource hungry, not anymore.