Created attachment 838691 [details]
Bash script to generate images for bug demonstration.

Hi,

although issue had been fixed (1134125) it is back. :-(

zypper search -s -i --match-substring xfdesktop
reports:
S  | Name                        | Typ   | Version            | Arch   |
Repository               
---+-----------------------------+-------+--------------------+--------+--------------------------
i+ | xfdesktop                   | Paket | 4.12.4-lp151.4.3.1 | x86_64 |
openSUSE-Leap-15.1-Update
i+ | xfdesktop-branding-openSUSE | Paket | 4.12.0-lp151.8.3   | noarch |
openSUSE-Leap-15.1-Oss   
i+ | xfdesktop-lang              | Paket | 4.12.4-lp151.4.3.1 | noarch |
openSUSE-Leap-15.1-Update

Attached script create_dcross2.sh needs bash, ImageMagick and exiftool to
create images for demonstration. It creates three jpg files with two lines
connecting corners (crossing in the center).

# set scaling (uses 4th workspace)
xfconf-query --channel xfce4-desktop --property
/backdrop/screen0/monitor0/workspace3/image-style --set 4
# set wallpaper (uses 4th workspace)
xfconf-query --channel xfce4-desktop --property
/backdrop/screen0/monitor0/workspace3/last-image --set <absolute-path>

Results:
* dcross-landscape.jpg gets centered but not scaled.
* dcross-portrait.jpg gets centered but not scaled.
* dcross-exif.jpg is rotated, lower left corner placed in lower left corner of
screen, but neither centered nor scaled!