We have seen that some sites offers to generate secure passwords even when you are not on a page where you would need to to generate a password (aka. a sign up page or a change password page). This usually occurs when the site is ambiguous about what kind of page it is. Does this happen on a particular site or all sites?
Note, that when this occurs while in the dropdown menu made by the grey asterisks, you can always click on the red and white asterisks icon in the drop down menu to change what action you wish to take for this login. The options are 'Saved Passwords' (gives you a list of saved passwords at this site), 'Fill' (form fills), 'Generate' and 'Disable' (puts the site on your Never URL list).
Pre-builds are generally newer than release. However, depending on the prebuild you have, it might be older. If you were using a prebuild for version 2.5, it will now be older than the official release of 3.0. If you are using IE 11 the prebuild and the download from https://lastpass.com/download