Thread:User talk:Nx/Edit conflict query

Don't take this as a "please Nx fix my idiocy", I'm just wondering if you'd know. I've had a few edit conflicts recently, but on closer examination they seem to be edit conflicts with myself. Then scrolling down the diff seems to be about replacing four tildes with the signature. So is this some internal glitch, like does the software do a "second" edit to replace the tilde code with the signature, or am I inadvertently double clicking the save page button? Just seems like an odd thing to happen.