Hi ! Shortform : in Dolphin, folders previews/thumbnails do not include video previews anymore. It used to be the case a few months back (I'm sorry I couldn't pinpoint the date). Explanation : a few months back, when folders previews/thumbs were enabled, one could see, in Dolphin, a selection of thumbs from all kinds of pictures / videos files, that were present in the folder, in the folder icon itself (provided, obviously, all relevant previews / thumbnailers were installed & enabled). It ceased to work a few months back on my 2 up to date Neon system. That is to say : folder icons still show previews of pictures files, but not of video files anymore (which was a nice feature to make it easier to preview the content of a directory). Of course, if you open the folder, video previews are shown properly. Installed : ffmpegthumbs 18.04.1 (As a side note : PDFs are not shown either, but it was not the case before and it's more understandable as show a quarter of PDF text document page in a folder icon is not really telling.) Cheers !
I can confirm. Even with video previews enabled, the folder does not show them. There was some work regarding default thumbnailers, and it is possible that "video" was accidentally removed. Nate might know more.
Hmm, off the top of my head, I'm not aware of any work that might have caused this. The recent change to ffmpegthumbs only added the optional ability to remove the filmstrip border. And with everything from git master on my KDE Neon VM, I can see video thumbnails on my folders that contain video files.
@Nate : to make sure if this had been fixed meanwhile, I started from the Neon "Developer-Edition GIT-unstable" CD, installed ffmpegthumbs and double checked. I get the very same behavior as on my stable Neon install : videos thumbs are displayed but they are not displayed within the folders icons. Maybe you still see some that were generated a couple of months ago ? In a specific directory ony my harddrive, I still see the videos thumbs in the folder icons. But if I move the files around, the video thumbs are not shown anymore.
At here the folder thumbnailer is following the default: 'don't show bigger files than 5M'. Earlier: https://bugs.kde.org/show_bug.cgi?id=238690#c16 . Making a new user with the clean set of the config files. Donwloading few sample files: https://samples.ffmpeg.org/MPEG-4/mpeg4conformance.mp4 https://samples.ffmpeg.org/MPEG-4/CDR-Dinner_LAN_800k.mp4 https://samples.ffmpeg.org/MPEG-4/MPEGSolution_jurassic.mp4 https://samples.ffmpeg.org/MPEG-4/video.mp4 Two smaller than the 5M and 2 bigger than the 5M. As default there is only 2 preview thumbnails. Adding a bit bigger size ( MaximumSize=52428800000 ) to the $HOME/.config/kdeglobals under the 'PreviewSettings'. Now the folder thumbnailer is showing all 4 images. A clip: https://youtu.be/EqW7jIubVgQ This with the Arch linux: Qt 5.11.0 KF 5.46.0 KDE Applications 18.04.1
Thanks Rog131. *** This bug has been marked as a duplicate of bug 238690 ***