I like to start typing whatever I'm looking for, in the browser bar. There a list will be populated with "suggestions" which I like to use (arrow down) to extent my search query and add some more words.

Safari expects me to "arrow right" or my (more or less) carefully crafted search will be auto removed (since the text will be "selected"). I fall for this x times per day (probably says more about me then about safari). Chrome will allow me to move to one of the suggestions and happily append my text without the need to "deselect" the text.

But there are more "usability" issues with Safari:

Why is the "x" to close a tab, on the left instead of right? Why do I need to press the ALT key to get the option to open a link in private mode (after a right click on the link)? Why can I not drag a URL to a bookmark folder directly? Why can I not re-attach a browser window as a tab in an open window?