Do you mean a scrollbar that appears on the right side of a web page, or a scroll area of a touchpad? Could you describe the exact steps to reproduce the problem?

For a mouse with a scroll wheel or a touchpad with a scrolling region, holding down the Ctrl key while using the wheel or sliding your finger in that region will change the action to zooming. I think there is a setting to disable that but I'd need to look it up if you think that is relevant.

Thank you, but it is the scroll bar in the webpage that's doing it. I put the cursor on the scroll bar slider and try to drag down to scroll, but as I do the webpage keeps getting smaller and smaller. It doesn't happen every time, but pretty often. Not sure if it's a Firefox issue or a "feature" of some other software that causes it. I do have a trackpad that will zoom (or shrink) by pinching...like you would on a touchscreen/tablet. So I suppose it could be related somehow.

I appreciate your assistance.

You're using a track pad? After moving the mouse pointer over the scroll bar, are you using tap/hold/drag to move the scroll bar "thumb" down the page? During that process, the "thumb" usually will change color -- for example it might be darker than when you are just sliding the mouse pointer around over it. Does it seem that it is getting selected successfully?

You're right, it appears to be a trackpad/user problem and not a Firefox issue. Appreciate you pointing me in the right direction.