File modify date is not updated in Finder file properties I have a video capture of a strange behavior:

File prior to editing:



Edited at 5:15PM using TextEdit

In Finder I see the file with strange rename, and Modified date value is not updated, nor does the length (at least a few bytes should have been added).



What is the cause of this behavior?

Unfortunately, since I only have a video capture and the issue does not reproduce, I don't know if the file changed back to its normal txt form. But it does not seem to change for as long as the video run.

Sorry for the ambiguity, I'm working on getting a more accurate reproduction.
The strange edited file name is due to it currently saving a temporary file. Did you quit TextEdit after you edited the file?