All loading and basemap gallery thumbnail images I've used since the creation of my app are saved when I download it. Is there a reason for this, is there a way to prevent it, and what is the best way to clean out the old/unused ones?
Go to your [install dir]\server\apps\[app#]\configs\BasemapGallery and delete all the unwanted thumbnails
Looks like this is what I needed. Thanks again, Robert.
If Robert's method does not work and you are still seeing unwanted images, it may be possible that it is an issue with your browser cache. You can quickly check this by opening your map in a different browser (one which you have not used to open it before) and/or clear your browser cache and try again.
Something similar happened to me, though it dealt with an image server and not what you're dealing with.
I think Robert has got me on the right track here. It's not that I'm seeing the incorrect image in the app, it's that when I download it to host locally I noticed it has a bunch of old thumbnail images that I'm no longer using. However, I have noticed that clearing the browser's cache does resolve other issues like you described.
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