When “Save Reply” happens while the internet connection is temporarily down (as just happened to me several times in this train), the content of the post are partially lost.
Steps to reproduce:
Start writing a reply.
While writing, cap your internet connection.
Hit “Save Reply”.
Some time later, restore your internet connection.
Expected behavior:
At some point, the “Saving…” process should give up and bring me back to the editor (or at least show a “Cancel” button that does this), so that I can try again to submit my response.
Actual behavior:
The “Saving…” bar at the bottom just sticks around with a spinning circle endlessly. The “expand” button it shows does nothing when clicked. The only thing I can do is to hit F5, which will restore some prior version of the post (not sure if from a local or a server-side cache) – but my last few sentences are lost.
I just had this happen 4 times in a row. At least the last two times I remembered to manually copy the post content before submitting, but that really should not be necessary.
Where are you seeing a “Save Reply” button? I am not aware of any such button in Discourse.
Drafts are saved automatically at regular intervals, provided the content has changed and there is enough content to save, beyond the minimum character limits.