SVG don't show up in thumbnail mode.
There is no preview for svg in thumbnail mode. If you try to open single svg file is open in thumbnail mode the application crashes. And where there are multiple images in thumbnail mode svg don't show up.
yeh, i have tought of it, @Dhruv-Vanjari originally only implemented svg for image mode, looking at the code implementing svg for thumbnail mode it seems there would be a need to create a cairo surface for the svg just like it is done with regular image mode but then figuring out a way to add that cairo surface long the other thumbnails, that or do some horrible hack to export the svg mounted into the cairo surface to a different image format like jpg and force the program to associate them as the same image somehow (not ideal)
i honestly haven't put much tought into it recently as the way i usually work with SVGs is in image mode and never open them on thumbnail mode 😅