Use the URL itself to include username/PW each time?
just realize if you do that, you maybe shouldn't bother with user security at all. Most everyone should realize that standard email is like a postcard (lots of people other than recipient can read it).
Also, I'm not sure what you mean by Browser Source that works in OBS.. In general, OBS composite's sources... you typically don't interact with the sources within OBS
And where are these users? typically 1 user per PC. And is OBS on that PC? if so, what do you mean by users (plural)?
If remote folks (or kids in classroom/whatever), or using separate device to reach website, then unless you are website admin and able to mirror sessin? or are you doing something to remote view each users screen?
sorry... I'm totally not getting your use case... and login method without interaction means next to no security (if not less than zero)... so please clarify