My browsers, both Firefox and Chrome, no longer offer a login page for Lastpass. This used to load when I opened a browser session but now we have a modal dialogue for sign in this feature has disappeared, as has the related preference in setting I think.
Can I get this back somehow, I don't want to auto-login but I do want to be presented with a log-in page or dialogue?
Could you try clicking on the LastPass browser extension icon, then clicking Account Options (or your email address/username, depending on your view) > Extension Preferences > Advanced and make sure that the "Open login dialog when browser starts" option is enabled? Once you save and log out of the LastPass extension, then restart your browser you should see the LastPass login page open in a new tab where you can log in to your account.
If you've tried the steps in the above comment, could you also try uninstalling the LastPass extension and reinstalling from here, then ensuring your settings are also the same to open the login dialog when browser starts? https://lastpass.com/download