I’m not sure if it’s Insync causing this or KDE, but I think it’s insync because this doesn’t happen with other directories.
I run KDE 5 on fedora 28. If I change the icon for my Google Drive directory from that garish blue default icon to the more uniform google drive icon (which looks like a regular Dolphin folder with a subdued Google Drive icon on it), it stays for a while but after a while it reverts to the default icon. I’m not sure what triggers it.
Is there a fix for this? Or can it be confirmed that it is actually not Insync doing it?