I installed a plugin for my browser to let me edit posts in a text editor for this reason — then the first time I tried it, it didn't fill the textbox when I saved and the editor window went away; I thought I had just lost a wall of text.
Fortunately, the buffer was still open in the editor, and I could switch to it in another frame, but still. Close one.
Yes, I've considered Firefox Notes or something like this for a while for just this one issue. But I rely heavily on blog editors to be "always connected/always saving", of sorts. Of course, in THIS case, the issue revolves around the fact that my WiFi drops out continually (because I tether to my phone), but saving the text "in-browser", would be good. I can and will continue to reply to things at The Midnight, but I may have to make an exception on composing full length entries, and just use Joplin Notes to write them out, then do a copy/paste job.