It's a pity because Joplin has pretty much the perfect feature set for me. I can't tell you much about the sync issue I had as I didn't find a solution (I also didn't spend too much time on it). Btw. I initially migrated from zim and the migration was super easy!!! What I can tell you is that Joplin suddenly didn't show any notes anymore because of a sync issue. In the source folder I saw some files still there but the notes of the previous week were all gone. I would have appreciated to have the option to tell Joplin that I don't care about sync and want my local Joplin files to be the primary ones - or something like that.
I then bought a 5 year plan of Standard notes which is not as user friendly as Joplin (in my opinion) but has some cool features (like the spreadsheet extension which is awesome). However, as mentioned, without being able to just paste images it's more or less useless for preparing blog posts or something like that. You need to use "fileSafe" I guess but for this you need Dropbox etc.. Other features missing in Standard Notes are simple drag & drop of folders and context menu...
Synchronization in Joplin concerned me too. E2EE is non-trivial to setup and Joplin will upload decrypted files if E2EE is misconfigured on a device. Encryption appears to be an afterthought in Joplin.
Standard Notes looks snazzy but too many features fail to work. I cannot get paste to work consistently on my mobile devices, and you're right - the editors are a an absolute mess. File Safe is only supported in unsupported editors and the supported editors lack basic features. FYI, the spreadsheet editor unsupported and exporting sheet data is...difficult.
I do not recommend Standard Notes anymore. Thanks for pointing out a need for external backups in Joplin though!
I then bought a 5 year plan of Standard notes which is not as user friendly as Joplin (in my opinion) but has some cool features (like the spreadsheet extension which is awesome). However, as mentioned, without being able to just paste images it's more or less useless for preparing blog posts or something like that. You need to use "fileSafe" I guess but for this you need Dropbox etc.. Other features missing in Standard Notes are simple drag & drop of folders and context menu...