I am having the same problem and thought it was operator error.
I am having a similar, if not the same, problem. My master password does not show, but on logging out I get a warning that I have entered my master password on a site. This only appears to happen when I delete the correct password that has been auto-entered on a site login page. The browser extension logo also turns a yellow/gold colour.
Pretty shocking service isn't it but I worked out that using Chrome instead of Edge fixes the issue, not ideal but will be moving away from LastPass soon anyway.
I can't believe this issue is 3 months old and no official response or fix