Hi, Firefox may display a scroll bar when the page is too long or too wide to fit the window. On Windows, Firefox tries to mimic the system settings related to width and whether the bar fades out/disappears. I set Windows not to hide it, so that is one option to consider. If you go to the Windows Taskbar search bar and type or paste show scroll the results panel should show

Always show scroll bars System settings

Click that to adjust the system setting.

Does that make any difference in your Firefox?

Setting the windows to always show scroll worked.

thanks