User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11_4) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/50.0.2661.86 Safari/537.36 Steps to reproduce: I just migrated from Apple Mail to Thunderbird v45 in OSX v10.11.4. I can work with my macbook whole day long with Apple Mail, but I need to find my charger at about lunch time after Thunderbird migration I also can feel the temperature on my keyboard after Thunderbird started for 15 mins Expected results: My battery usage can back to normal

When exactly did you install? When did all the imap mail finished syncing? Is the progress bar constantly "running" as described in bug 562977?

I installed TB45 4 days ago, and my email is POP3, not IMAP. I referred bug 562977, and I tried to make the changes below, let me observe the battery usage for few days first. layers.acceleration.disabled -> true layers.offmainthreadcomposition.enabled -> false

I just had a 4 hours meeting in customer's office, and both temperature and battery usage went back to normal, 20% battery was used. I considered the case is closed. Thanks Wayne.

You may have a workaround, but there is still a problem :) So duping

ivanluiok, Followup questions... 1. The settings in comment 2 are the default, which suggests you may have overridden the default by enabling HWA. Do you recall changing the value at Preferences > Advanced > General > Use Hardware Acceleration? And what is the value there now? 2. What model macbook and video?