Some websites, such as news websites that utilise paywalls, currently block Incognito mode browsers because they can't be tracked by tools such as cookies.
One of the most common ways for these websites to do this is to attempt to use the FileSystem API, which is blocked by Chrome's Incognito option as it can be used to create permanent files on the user's computer.
Google's plan to combat this technique is to create a virtual FileSystem utilising RAM, which ensures that any data is deleted permanently once you leave Incognito mode.
An internal design document reportedly said that once this fix is in place, Google will switch its focus towards removing the FileSystem API altogether.
According to the document, the functionality is expected to arrive in Chrome 74 as an option that users can manually activate, It is expected to become a default setting for Incognito browsers two versions later.