I've read that Apple has fixed the problem, yet I'm still experiencing the problem.
To work around the problem so you can enter website addresses into the address area, go to Preferences, then click the Search tab. Remove the tick from Include Safari Search Suggestions. Close and reopen Safari.
I suspect his problem should be solved over the next few days so when you want to, you may wish to enable the setting again.
For those interested, one thing which helped me through this issue was I had my site www.AdvancedSearch.com.au/SearchAustralia set up as the home page, and to also open when new tabs were opened. I could still use my search site to search for what I wanted. My search engine enables me to enter website addresses and go to the site, whereas most search engines will send you to a list of search results. Initially I thought because I have an extension loaded to use this search engine, it may be causing the problem. I disabled the extension but found no change. That made me look further afield to find if there was an issue and thus I found this problem was affecting many users at the moment.
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