Samsung Link internal storage of network photos' thumbs
If I download photos onto my home network PC from another camera, and if I do *not* download them (manually, automatically or otherwise) directly to my Galaxy for internal storage (either sdcard0 or extSdCard), these photos nonetheless appear in the "My Recent Content" section of the Samsung Link app on my Galaxy. This makes sense, as my home network system (where we also have a Samsung smart TV) runs Samsung Link, and the Galaxy and PC are both "registered devices" that Samsung Link accesses for sharing data among all registered devices. Yes, I can choose to download photos from the network for permanent storage directly on the Galaxy, but I do not always do so. I have noticed that, even when the home network PC is turned *off*, the Galaxy phone's Samsung Link app still shows in its "My Recent Content" section those photos most recently added to the PC / Network- and I can touch them to view them individually. They are not available for viewing on the phone in any other way ("My Files", "Gallery", "[Google] Photos", etc.) Note that I do *not* have any Cloud storage mechanisms in place or involved. This all says to me that the phone's Samsung Link app is maintaining [at least] thumbnails of those few (maybe 15 or so) photos most recently added to the home network PC. I have looked all over though, in the device's storage (both sdcard0 and extSdCard) and in the directory folders and caches, but cannot seem to find them. I did come across many system files for which I do not have app to open, and I suspect that the thumbnails are somehow condensed into one or more of those data & cache files on the device's storage.
So, my question simply is: Where precisely does the Galaxy's Samsung Link app store those thumbnail files locally on the device? The Samsung folks are very nice, but they keep running me around to Device support, then to App support, then to Device support, then... I suspect it is because the folks on the front line do not really know themselves. Thanks a bunch.
(My Galaxy S3 is T-Mobile SGH-T999L (LTE) and runs Android Jelly Bean 4.1.2 & Samsung Link 1.6.1129.)