Whatever the problem was, it has now, following a reboot, disappeared (on all filesystems that I've tried).
I'm not sure whether that's good or not.
If it recurs, I'll try to do some reasonable investigation before posting what I find here.
Just for background, I have quite a few filesystems mounted, each with its own trash; a typical entry in the .trashrc file looks like this:
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[/tmp/.Trash-1000] Days=7 FixedSize=500 FixedSizeUnit=2 LimitReachedAction=1 Percent=1 SizeLimitType=0 UseSizeLimit=true UseTimeLimit=false
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and autotrash is run daily (overnight) with the parameters (for the above filesystem): -d 35 -T "/tmp/.Trash-1000"
/tmp is never cleared on boot.
All filesystems are treated the same way as /tmp: the same .trashrc entry and autotrash parameters, just with different mounted names for the trash directory.
Anyway, if it happens again, I'll be back with more info.
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