Beginners • Weird VNC Remote Desktop Issue

Hello everyone, I‘m just a rookie for pi and English, so plz understand me.
When I used vnc to connect the my pi 4b, the desktop became so weird that I can't find a short and precise sentence to describe it. That is the reason I register this forum.

I tried to make my window in pi full screen, like this browser in my windows OS:
https://ibb.co/DGysjbv
but in my pi, it would become this:
https://ibb.co/syG6TXx
That is you've seen, the window is not full with the whole desktop. It's weird. And when I click the right mouse button in some special area, the appeared menu will appear a weird area, just like there's a wall blocking it (The yellow arrow is where I clicked the right mouse button.):
https://ibb.co/pQKpH2b

I would also like to add some more information. I am using headless environment, thus vnc is the only way to access Desktop for me. The OS running on my pi is raspbian.
So that's it. Does anyone have any suggestions? Thanks! And I'm trying to understand this forum's format of posts, so this post looks rough. SRY

Statistics: Posted by hasir — Thu Mar 14, 2024 4:25 pm

---