This is an ankh, the Egyptian hieroglyphic character (generally) representing eternal life. When you come across your next form to fill out, you may notice the little yellow icon in the corner of the textbox (as seen in the top image). Then restart your browser to make sure the extension/add-on will be active for all tabs you have open. Get started by grabbing a copy of Lazarus for your Chrome or Firefox browser. It's not new, but you may wonder how you've had the patience to continue filling out online forms without it.
This extension will save the data you type into those pesky textboxes, and will allow you to re-add it with just a couple of clicks. For situations like these, there's an extension for Chrome called Lazarus. If you're filling out your car insurance quote form, writing a comment on a blog or filling in payment details for food delivery, it's annoying to lose what you've already entered because of a server error or accidental mouse click.