@leocg Thanks for your response. To use any online service almost always requires a "password", thus, by definition, the htpc would have "sensitive" content in the form. The question is whether the access to the "sensitive" content is available to any user or just a select few (administrators). A password to block settings makes the most sense. An alternative is to not use a web browser as an htpc interface, but it's the power that an web browser can supply that makes it the most useful interface compared to something like plex or kodi. A web browser is an all-in-one solution for all media types from movies, live tv, news articles, music, games, etc. A Smart TV/Roku can do some things a web browser can, but a web browser can do almost everything in comparison and usually far better.
Add the power of Windows too and you can now have an htpc with PC games, Xbox streaming, Game console emulators etc. A password to lock access to the Password Manager just makes much more sense than to limit the system.

@sgunhouse Thank you for your response, but since the PC is used as a HTPC, the default windows login is set to no password. As such, if the HTPC was powered down (at night, or say a power cut do to a storm), any user of the system would be able to log back in and then use Windows and Opera etc. If the login was password blocked, then everyone would need the password just to enter (inconvenient if you are using a PC as a TV). A simpler solution would be a password to lock to the browser's Password Manager. Better still would be a password to lock the browser's "Settngs", that way users wouldn't be able to change anything in the browser, (this could also be adapted to block users from changing things like wallpapers, Speed Dial buttons etc.).

Hi. I love Opera for it's innovation and always being ahead of all the competition, and use Opera One and it's Speed Dial as one of the many interfaces of my Home Theater PC System (essentially I'm using a PC as a TV). As such, the PC is always on and logged into Windows (by the default user) and anyone can then use the PC, and the Opera One browser and (via the Password Manager) login to websites like Amazon Prime, Netflix, DisneyPlus etc. However, this also means that anyone can access the Password Manager through 'Settings' and reveal (and potentially steal) any userid and password info. Obviously, this is a big security hole. The issue could easily be resolved if Opera had a Settings lock or Password Manager lock.
Is there such a 'lock'? If not, can the programmers please add a locking option for users who use Opera for scenarios like this?
Thank you in advance.