In all major Internet browsers (e.g., Chrome, Edge, Firefox, IE, Opera), pressing Ctrl + Shift + Delete opens the Clear browsing data window to quickly clear private data and history
Does it still happen?
If so try starting your browser with apps disabled.
Does it still happen?
If not, one of your browser add-ons would appear to be connecting to this site.
Now it is a bit of a pain, disabling one app at a time to find it.
Start with any app recently added and or apps recently updated.