piles up every file opened via file manager

[SebiderSushi]

If i open a file in document viewer from within a file manager, it gets copied to the "files" directory at the "Cache location" of the document viewer.

As far as i remember, with every device on which i have used document viewer, this leads to an infinite pile-up of temp files. Never did i consciously encounter any automatic cleanup of these files.
Since many files i deal with can be a couple megabytes in size, the temp files can grow quite significantly in size.

Is there any setting to prevent this?
Why is it necessary to copy the file prior to opening it?

Additional info:

• I'm only dealing with .pdf files
• I've been using document viewer on android versions 6 to 10
• I'm using either the proprietary file manager nextapp.fx or the preinstalled android file manager to open files. Both of which would be using a content provider to pass any opened files along to the document viewer as far as i know.

[bjamesv]

I would agree, 10+Gig consumed on my Android 11 device.

I near exclusively use the stock AOSP Files browser when opening documents (typically a few kb to 100+Meg size). Never made the connection, but file cache does seem to be what's sucking up device storage.

[acornsirup]

If the mechanism is required for caching purposes, the files should at least be categorized under "Cache", making it easier to clear them.

[kolAflash]

I'd really appreciate a fix for this!
(one which doesn't require user interaction!)

If a user doesn't know about this it's really a problem!
And it's a reason for me not to suggest Document-Viewer anymore to other people.

I wouldn't wonder if people bought new phones and threw away the old ones, because they thought the old phones just didn't have enough storage for their usage behavior.