Comment by hadik
7 hours ago
I have my vault saved in iCloud Drive and solely access it from a single device.
We all know about iCloud Drive being known for being somewhat unreliable and sometimes causing sync issues, but I don't really see this type of bug being caused by it. I would be more suspecting if files were corrupted or changed in some other form than being replaced by other notes' contents.
The kind of issue points to Obsidian as the cause to me. Some commenters in the discussion I linked were hypothesizng about some kind of race condition or rare bug when opening two different notes in the same Obsidian window/tab in sequence and suggested using an extension that works by opening each note in a new tab, which I haven't tried. I try to work with as few extensions as possible to reduce any kind of attack risk.
I am very open to help or different interpretations of what I experienced though.
Make sure to set your Obsidian folder to "Keep downloaded" on iCloud for every device. Otherwise iCloud automatically deletes files locally to save space on your device.
It's a terrible default and Apple doesn't provide any way for developers to detect if it's off.
Thanks for the advice. I have "Keep downloaded" enabled already for all my devices, so it does not seem to be the cause for this issue, although I am sure it may be a factor for others.