[closed] Is there a way to make the JOSM tile cache persistent?

I'm working with the Scanned USGS Topo imagery layer almost daily as I try to add geographic details to the state of Alaska. The USGS Topo map layer is invaluable in this work. However, in recent months the imagery server does not reliably supply tiles at high resolution leaving me working with imagery of such poor quality I can barely read the names of things. This is a known issue and I'm not sure there is a solution but at any rate, that's not what I'm asking about.

Today, for some reason, I'm able to see the "good tiles" in the region I'm mapping. My question: if I spend time panning around "gathering" high resolution tiles in JOSM's tile cache, or imagery cache, not sure which is which, can I somehow retain those tiles for future sessions? The data in the USGS Topo maps hasn't changed for years and an "old" tile or a newly retrieved tile should be identical month to month, year to year. So, I'm wondering if there is any way to either store these tiles locally, or better yet, to prevent JOSM from refreshing its USGS Topo cache?

Dave