If "Preview generation failed" for some images in the Files section, how do I trigger a new attempt. (The images are ok, they render properly in full browser window size.)
Hello mprove,
first you can try to delete the whole image cache from your browser and make a hard reload.
Otherwise you can connect via finder to your protonetbox and enable “showing of hidden files”. Then you will see a “.protonet” folder. In this place are the thumbnails for preview stored. You can delete this folder and refresh the page in your browser.
This should help.
Best regards;
Markus B.