what is responsible for the refresh of tab in safari tab overview

[65301361]

I found my 2017 radeon pro 580 iMac with 2tb fusion drive will refresh the thumbnails of the tabs every time I open "overview"(the button is on the right top of safari a little square) but my 2015 MacBook Air will just show all the thumbnails immediately without refreshing. they are both 8g btw. what could be the problem?

 

[mikehalloran]

Check your preferences

 

[65301361]

Check your preferences

hi which part of preference you meant?