As it is, I have no idea what the Maximum size of chest should be set to. I don’t even know where to look for this–in fact, I don’t even know, for sure, if this is a file, or what! So, if you indicated the current size of the “chest” [or expected size, or average size, whatever would be meaningful, here], that would, at least, provide some sort of reference.
And consider doing this for other instances, such as Maximum size of each log file, and Delete scan logs older than [e.g. show statistics that would make it easier to judge how many days to set that to–such as average growth of scan log/day], ya know, stuff like that
Well what is displayed in that screen ‘is the current maximum size.’
Whatever figure you set in there (or the default 256mb) is the maximum size it is allowed to grow to.
The 256MB default is a reasonable limitation as it leaves room to expand, for many people this value is unlikely to reached. It doesn’t mean that 256mb of space is allocated for the chest, just not to exceed that limitation.
You can set your own limit, or as indicated set it to unlimited ‘0’ value.