I have a dual boot Win 10/Debian setup on my laptop. I have not touched the Windows boot in months. There is nothing on there that needs saving.
How can I ditch the Windows partition and make it available as free space in Debian without damaging my Linux setup?
Gparted, you can delete the Windows partition and resize the Linux one to fill the space.
This should go without saying, but I’ll say it anyways: backup any important data beforehand, just in case.
Preferably image the whole disk to some file on another disk so you can unfuck anything that gets fucked.
This only works for people who have disks lying around big enough to backup their entire primary disk
And make sure you save any important data on the Linux partitions, don’t just assume that /home or /sys will be there after the resize.
And your partition must on the right (I think?) To merge to the main disk.
This is the way :)