I'm running High Sierra on my older iMac with 16 GB of ram. I use Safari and I often have 5 or 6 websites open at once. Throughout the day I will very often encounter a website that will produce the following message at the top of the webpage:
This webpage is using significant memory. Closing it may improve the responsiveness of your Mac.
This happens a lot and Safari becomes sluggish on all the other webpages as well. This happens to sites I want to use so closing the webpage is not the best option.
I haven't noticed this in the Chrome Browser but I haven't used that browser very often and would like to continue using Safari. What is causing this to happen and is there a way to stop it?