Do I need a sync source?

[markrenier]

Operating system

Windows

Joplin version

2.14.20

Sync target

File system

What issue do you have?

Hi! I got a new SSD USB device the other day and migrated my JoplinPortable installation from a slower device by exporting and creating a JEX file on the old device, then importing it into the new JoplinPortable installation. Works great, and solved my "trailing nulls" on some of my notes that I didn't want to delete.
Before I imported the JEX on the new device, I played around a bit, adding a note, editing the default 5 notes, and so on. These edits were retained, even before I set the File System as a sync source. Now I've used Joplin on my mobile phone and synched to remote files, before my system got sluggish while synching, which resulted in my setting up everything on a USB stick.
Can anyone explain to me the default operation of a JoplinPortable installation that has not yet been set up to point to a file source? What is going on here? Do I need to set up a file system source? What happens if I don't set up any source? I guess I'm trying to understand the Joplin sync philosophy.
Thanks.

[ajay]

Either you are (getting) confused about file sources and sync targets (that's what I read "into" your post), or I do not understand your post. Even if this is my fault, it may be worth explaining a little better so others can catch up. Good luck !