Yes and no. Inherently, about:blank web pages are not harmful to your computer or device. They're a part of the system, so occasionally seeing the page isn't a big deal. However, it's likely an underlying issue when you see about:blank pages frequently. For example, if your internet browser is compromised, you may see this page rather than your home page. If you frequently see something without user provocation, it's a good idea to run a security scan to be safe.