I am using xplanet to render my screen background images.
After kde4 had removed the possibility to directly render to the X root, the workaround was to select  a directory for viewing in slideshow mode, and have xplanet render the image into a file in this directory.
This no longer works with plasma 5.7.4 (openSUSE Tumbleweed), a change of the file is ignored and only the first version loaded when starting plasma is displayed

Reproducible: Always

Steps to Reproduce:
1. create directory, put a jpeg image there
2. Desktop Settings-> Wallpaper Type Slideshow ; add above folder ; set to change every minute
3. change the jpeg image

Actual Results:  
plasma still displays the original version of the image

Expected Results:  
show the changed wallpaper

I tried creating a link in the directory, pointing to the other file.  But even then changes are ignored and only the (internally cached?) version is shown.