This morning one of my collaborators sent me a somewhat anxious email, asking why Dropbox was notifying her about changes to lots of shared documents. I checked and found that my Dropbox client was syncing thousands of files, including many that I haven't opened in years.
I looked at one of the synced files in the web client. It shows that the file was modified today, but when I look at the version history it says that this is the original version, which was uploaded in 2013 and has never changed. There are no changes shown in the Dropbox log, either. (The screenshots below might make this easier to follow)
When I look at the affected files on my computer, some of them show a modification date of today, and some appear to still show their original, correct modification dates.
I'm using Dropbox v3.8.6 on Mac OS 10.10.4. I haven't moved any folders, done blanket permission changes, restored from a backup, or done anything else that should have touched a bunch of files.
What could be causing Dropbox to sync all (or possibly just many) of my files? Is there any kind of change that would not consistently alter the modified date on my filesystem, but would alter the modified date used by Dropbox?
A bunch of files show recent modification dates...
But when I right-click and look at "previous versions," the file shows no changes.
And the Dropbox log doesn't show any changes at that time, either.