Currently, it is only possible to have a slideshow with automatically changing pictures in fullscreen mode. It is not possible to resize the slideshow window to occupy, for example, half of the screen. It would be nice to have such a feature. For me, the use case would be that I sometimes like to have a slideshow with relaxing imagery in a corner of the screen while working. I am currently using another image viewer (feh) for this purpose. If I recall correctly, the slideshow window used to be resizable with the quick-tiling shortcuts in the past, but it is not possible to resize the window now. I am not sure exactly when that ability was removed.
Hello, I signed up to second this request. Gwenview is one of the best and most efficient OOTB image viewers on most platforms. However, I noticed no way I could enable the slideshow mode to cycle images while in windowed mode. The most common use cases is to have two windows side-by-side each running a slideshow. Instead it forces fullscreen mode. Since we have larger screens these days and depending on source media, having only one slideshow is limiting. It is the only feature missing from Gwenview for which I'm forced to seek an alternative. Cheers