Assume the custom icon is a photo of size e.g. 512 x 512. I'm not talking about zooming in nautilus with Ctrl+mouse wheel, but rather of the size of custom icons relative to the size of thumbnails. The visible size of thumbnails of regular files with image data can be increased e.g. via:
gsettings set org.gnome.nautilus.icon-view thumbnail-size 256
When I do this for regular files, how can do the same for the visible size of custom icons of folders and symbolic links? At the moment my thumbnails are large and the custom icons are small, which looks asymmetric and also does not allow to recognize details in the custom icons.
Example:
#!/bin/bash
image=/usr/share/icons/hicolor/512x512/apps/gnome-chess.png
cp $image .
mkdir dir1
ln -s dir1 link1
gvfs-set-attribute dir1 metadata::custom-icon file://$image
gvfs-set-attribute link1 metadata::custom-icon file://$image
nautilus . &