Constant keyboard lag and Safari beach balls, significant energy issues.

[iMore Question]

I have a 2015 MacBook Air running latest version of High Sierra on 8 GB of RAM. Constant beach balls and keyboard lag on Safari. I also get the occasional, this website is using significant memory in Safari. No extensions are running. Only Microsoft Word 2018 and Outlook opened. OneDrive and Wunderlist are opened in background. 60 GB free space with 128 GB original. Computer hardware, OS, or Browser issue? Had my SSD replaced last year at Apple Store due to failure.

 

[Just_Me_D]

Start from scratch and reinstall macOS. That’s my recommendation.