Edit: After half day, my wife’s Mac started having the same problem. I have then applied the solution that I found in the Apple
Creating a Safari “Home Page Button” on iPad
Unfortunately, there’s no home page button in Safari on iPad. The most convenient way to get it is to create a link in the Bookmarks Bar:
1. Make the Bookmarks Bar visible by touching Settings, Safari, Always Show Bookmarks Bar.
2. Add the homepage to bookmarks by touching the + icon near the address bar.
3. Enter the bookmark name, such as “Home”, leave Bookmarks Bar as the location where to keep the bookmark, and touch Add.
Now you’ll be able to navigate to your home page with just one touch!