The Widget Box (initially located on the left side of the Qt Designer) has a really big singleStep size. This means that scrolling with a mouse wheel immediately jumps to the middle of the scrollarea. Depending on the window size I often accidentally skip entire sections, wondering why I can't find the widgets I'm looking for.
This has been very cumbersome to use since as far as I can remember and I don't really know why I haven't opened a ticket for this up until now.
This offset here was achieved from just a single mouse wheel step: