having a drafted feedback comment should stop you from navigating away

just now, i was writing a comment on this feedback site and wanted to include a link to an adjacent comment. i clicked "Permalink", hoping it would copy to my clipboard. instead, it took me to the permalink, and when i navigated back, my drafted comment was gone.

the website should employ the standard browser API that asks you "are you sure you want to leave this site? there are unsaved changes" if there is any risk of data being lost when the page is closed.

i'm used to Sharkey (microblogging), where you can navigate away from any note compose view without confirmation. you can even reload the page, and as soon as you hit "reply" on the same post as before, it will restore your draft. this is really convenient on mobile, because it means i can "multitask" and research in the same application and provide references/links to other posts, while writing my own. but it has privacy implications: should everything the user types automatically be synced to the server? it's essentially a keylogger. many sites do communicate this kind of behavior clearly; most often by having a little notice under an input box that says "This draft is saved and will not be lost if you reload the page". i don't remember where i've seen this, but usually that notice will become a refresh animation during syncing, which triggers after a second or two of inactivity while typing (and when you begin typing again, the notice turns into "Unsaved changes" until it syncs during the next inactivity)