Welcome back, Albert. Thanks for the quick update, and no worries at all about not being very good with computers. You’ve done a great job explaining what happened.
And don't be too fret. Based on what you described, it sounds like your computer may have just temporarily entered full-screen mode and experienced a display glitch. This can happen when your device is old, you have too many tabs open, or the tasks are overloaded. These kinds of issues can sometimes resolve themselves after a restart or when the system refreshes. To avoid this in the future, I suggest you restart weekly, and update your Windows/drivers if possible. You may try to ask the youngsters around to take a look!
As for the thin scroll bar, you can make it easier to see by adjusting a setting:
- Click the Start button > open Settings
- Go to Accessibility > Visual effects
- Turn Always show scrollbars to On
This will keep the scroll bar visible and easier to grab, which should help with your eyesight. I also have other Registry fixes that can forcefully make the bar bigger, but they are quite advanced, so I skip them this time. If anything disappears again or you’d like help adjusting other settings for visibility, feel free to come back. I’ll be here to guide you through it step by step.
If you think any of my answers was helpful to you, it'd be appreciated to click "Accept Answer" and upvote it. Warm thanks!
Lychee-MSFT | Microsoft Q&A Support Specialist