OK! I've been happily using Joplin 1.7.11 on my Ubuntu 20.04 Desktop.
All told I have less than 2000 notes, around 100MB worth.
It is successfully synced (with encryption) to Dropbox.
I recently bought an Android phone. I installed Joplin, synced it to the same Dropbox account. I can see all the notes there, but they are encrypted and I am not being prompted anywhere for the password / encryption key.
On the phone, the little synchronize wheel is still spinning with the word "Cancel" and it says "Fetched items: 7/500."
The next line says "Cancelling..."
The phone has been in that state for quite a few hours now....
OK! I've solved this, but it was in a bit of a backhanded way. That said, it may help someone else so here it goes.
Before anything, I backed up all of my notebooks to a .jex file -- something we should all be doing anyway. Then, I spent many hours tinkering and deleting and trying to sync. What eventually worked was exactly this, in this order:
I deleted the Joplin app from my Android phone and I completely deleted it from my Ubuntu desktop (the hidden .joplin folder in the home directory and @joplin and joplin-desktop from .config).
I also went into my Dropbox, and completely deleted the Joplin app folder, going into the trash on Dropbox to permanently delete it.
Next, I downloaded the App to my Android phone and immediately created an encryption password for it. Then, I linked it (and synced it) to my Dropbox account. Quick and easy, since I had not created any notes yet.
Then, I installed Joplin on my Ubuntu desktop, used THE SAME encryption password as I had on the phone, and then also linked and synced it to my Dropbox account.
Who knows why, both the app on my phone and the desktop app both asked me to re-enter the encryption password a second time. So, the Ubuntu desktop has two identical encryption passwords and the Android app has the same two identical encryption passwords.
I did a few test notes -- one on the mobile phone making it sure it showed up on the desktop, and one on the desktop making sure it showed up on the Android phone and it all worked -- success!
Finally, I took my backup .jex file and imported it on the desktop. I waited for it to sync (which thankfully, it did error-free) and then, in the moment of truth, opened the Android app to see if all of those notebooks and notes in the backup file would sync there -- they did!
A few more test notes, syncing and deleting and I feel confident and good to go.
That all sounds pretty simple, but it took many hours and testing different scenarios to reach that. I hope it helps someone.
The encryption documentation specifically states that the notes have to be encrypted on one device only. On the second device the notes will be downloaded encrypted until you get a prompt to enter the decryption password (which of course is the same you picked on the first device).
A previous sync algorithm might have only retrieved the master key at the very end. But I think that sync version 2 retrieves the keys in the beginning. Unless I'm mistaken.
Laurent would know for sure.
I do believe you. You can see my first round of errors above in this thread. I spent hours trying to get this to sync properly and installed and deleted and reinstalled (both on the desktop and on the phone) many times over. My "solution" above is the only thing that finally worked.
