A note or a sentence typed in the seconds before you closed or reloaded the tab could go missing from the saved copy until you next opened that document on the same device. It now reaches the server on the way out, every time.
The same fix removes a rare false alarm: on a slow connection the Tome could tell you a document had been "changed somewhere else" when the only other writer was you, a moment earlier. That message now appears only when it is true.
How to use it
Nothing to switch on. Type, close the tab or reload, and the words you just wrote are in the document when you open it anywhere else.
If you did lose a line this way before the fix, open the document on the device you wrote it on: the local copy is still there and is saved as soon as the document loads.
The "changed somewhere else" dialog still appears when it should — when the same document really was edited from another device or tab — and still lets you choose which version to keep.