Just this week one of my users noticed that the autocomplete capability has stopped working on inputs for list item forms. All of the previous values that she'd been able to use to quickly enter in her list items have disappeared. Even when she enters new items it doesn't allow autocomplete for ones that she had just entered. Also, this has happened at the same time to other users who use the same form. I've even tried it with both Google Chrome and Internet Explorer on my own computer and I experience the same issue.
After reading up on autocomplete it sounds like a "name" attribute is required in order for it to work. When I use Chrome Developer tools to investigate one of the input tags I can see that there is no "name" attribute.
Did Microsoft update SharePoint Online and stop using the "name attribute on list item forms?