Display scroll bar for longer
Run

defaults write -g NSOverlayScrollerHideDelay -float 3


where 3 is a value in seconds and quit and reopen applications to apply the changes.

I found the preference key by running mdfind kMDItemContentType=public.unix-executable -onlyin /System|xargs strings 2&gt;/dev/null|grep -E '^[[:alnum:].-]{10,80}$'|grep -i scroll.