Created attachment 7937
The attached patch makes significant improvements to the layout of the xfce4-diskperf-plugin preferences dialog. These improvements include making labels and fields align nicely and applying the standard 6/12/18 spacing rules from https://developer.gnome.org/hig-book/2.32/design-window.html.en
I'm also attaching a before and after image to easily see the changes.
Created attachment 7938
Before and After Screenshots
Sean Davis referenced this bugreport in commit a83da46240833c8b8b96897a6d30efbe1a8c11d2
Improve spacing in settings dialog (bug #14663)
Thx for the patch, and sorry it got totally forgotten...