Modification dates of folders are being changed during sync

[shape55]

Hi, I recently installed and started using Syncthing for the first time, and from the very first sync have experienced critical issues w/ the app destructively editing modification dates of folders, and breaking/rewriting alias files (rather than syncing them) on both computers. I’m using v1.30.0 to sync between 2 MacBook Pros, one using Sequoia 15.6.1 and the other using Catalina 10.15.7, but both issues also happened on the previous 1.29.7 version of Syncthing.

Many folders and a small portion of files that haven’t been opened/edited since well before installing Syncthing have had their modification dates updated to the time of sync, and then moved to the top of the folder above the Syncthing “.stfolder”. This pushes all of the recent folders (w/ accurate mod dates) way down below a long list of very old irrelevant ones (w/ inaccurate mod dates) that have floated to the top. Therefore, if you sort by Date Modified it throws everything out of order, which makes them useless for my purposes.

This prompted me to replace all of these files w/ backup copies just to restore the correct mod dates. Though tedious and time-consuming, initially I thought this would provide a workaround, but the backup copies which now have the dates corrected and matched to the files on the other laptop trigger the exact same issue on it. But there isn’t any discernible pattern that I can see. If the same folder on 2 shared devices has a different modification date, then it can’t be synced, but in these instances Syncthing recognizes them as such.

Also, if I Stop or Pause All Devices on either laptop, the sync still runs for a while, changing mod dates of folders/files as I watch them in real time float to the top of the parent folder. I have to quit the app in order to get the process to stop right away.

Very surprisingly, 0 issues turn up when I searched this repository for alias or modification date. Considering that an even more critical issue happens during the sync process with rewriting alias files and replacing them with Syncthing text files, it would seem that preventing the app from modifying files that it syncs would solve both issues. I’ll create a separate issue for aliases.