I tried mounting a hard disk partition, and now it prompts me every time

So, once again, I performed an innocent-looking action in Linux, and not I can't put it back the way it was before. The other day, I was trying to find something in the file system. (Usually, I use Dolphin, but this guide said I could find it more easily in Nautilus/Files in gnome.) While inside the "Files" app, I clicked on "Other Locations", and one of my hard disks was listed there. After clicking on it, I was prompted to mount that partition. I did not want to mount it, as it is one of the boot partitions, and was already mounted. But now, each time I restart the computer, the same prompt pops up on login. I have mounted it, and unmounted it. Everything is fine, it just mounts the already exisiting "/boot" partition to "/media/$USERNAME" which is silly and unnecessary. I have: * looked through Autostart * looked through my list of devices * modified "/etc/fstab" and added this particular UUID with the "noauto" option Nothing seems to change, either good or bad. **How can I find this location and get rid of the prompt on each login?** *(The removable devices panel was interesting, as it had this trouble partition all by itself under "Attached Devices", but I cannot seem to make any changes here, or mark it to NOT be automatically mounted.)*