In my laptop I have a second drive that is just for storage. Movies, music, documents etc. I have this mounted as shown below:
# Static information about the filesystems.
# See fstab(5) for details.
# <file system> <dir> <type> <options> <dump> <pass>
# /dev/sda2
UUID=58fa66da-b2ba-47d5-9cfc-f415c3fe9a84 / btrfs rw,relatime,compress=zstd:3,ssd,discard=async,space_cache=v2,subvol=/@ 0 0
# /dev/sda2
UUID=58fa66da-b2ba-47d5-9cfc-f415c3fe9a84 /.snapshots btrfs rw,relatime,compress=zstd:3,ssd,discard=async,space_cache=v2,subvol=/@.snapshots 0 0
# /dev/sda2
UUID=58fa66da-b2ba-47d5-9cfc-f415c3fe9a84 /home btrfs rw,relatime,compress=zstd:3,ssd,discard=async,space_cache=v2,subvol=/@home 0 0
# /dev/sda2
UUID=58fa66da-b2ba-47d5-9cfc-f415c3fe9a84 /var/cache/pacman/pkg btrfs rw,relatime,compress=zstd:3,ssd,discard=async,space_cache=v2,subvol=/@pkg 0 0
# /dev/sda2
UUID=58fa66da-b2ba-47d5-9cfc-f415c3fe9a84 /var/log btrfs rw,relatime,compress=zstd:3,ssd,discard=async,space_cache=v2,subvol=/@Log 0 0
# /dev/sda1
UUID=019A-EC93 /boot vfat rw,relatime,fmask=0022,dmask=0022,codepage=437,iocharset=ascii,shortname=mixed,utf8,errors=remount-ro 0 2
UUID=85265f87-225d-4c7d-8b77-39a0cdeced38 /mnt/Storage ext4 defaults 0 2
The very bottom entry is the second drive - '/mnt/Storage'. (the 2 at the end was a zero, I have changed it just now to be numbered as my boot drive to see if that made a difference.) This is mounted and started when I turn the system on and I can access it and use it as normal without issue, but in Firefox and any other program that allows saving to disk, I cannot set my download save location to this drive. If I go into a programs settings to try and select this as a save location, it is not listed. I'll put a screenshot of this in the comments. I dont know what other information to provide alongside this so Il leave it at this for now.
# Static information about the filesystems.
# See fstab(5) for details.
# <file system> <dir> <type> <options> <dump> <pass>
# /dev/sda2
UUID=58fa66da-b2ba-47d5-9cfc-f415c3fe9a84 / btrfs rw,relatime,compress=zstd:3,ssd,discard=async,space_cache=v2,subvol=/@ 0 0
# /dev/sda2
UUID=58fa66da-b2ba-47d5-9cfc-f415c3fe9a84 /.snapshots btrfs rw,relatime,compress=zstd:3,ssd,discard=async,space_cache=v2,subvol=/@.snapshots 0 0
# /dev/sda2
UUID=58fa66da-b2ba-47d5-9cfc-f415c3fe9a84 /home btrfs rw,relatime,compress=zstd:3,ssd,discard=async,space_cache=v2,subvol=/@home 0 0
# /dev/sda2
UUID=58fa66da-b2ba-47d5-9cfc-f415c3fe9a84 /var/cache/pacman/pkg btrfs rw,relatime,compress=zstd:3,ssd,discard=async,space_cache=v2,subvol=/@pkg 0 0
# /dev/sda2
UUID=58fa66da-b2ba-47d5-9cfc-f415c3fe9a84 /var/log btrfs rw,relatime,compress=zstd:3,ssd,discard=async,space_cache=v2,subvol=/@Log 0 0
# /dev/sda1
UUID=019A-EC93 /boot vfat rw,relatime,fmask=0022,dmask=0022,codepage=437,iocharset=ascii,shortname=mixed,utf8,errors=remount-ro 0 2
UUID=85265f87-225d-4c7d-8b77-39a0cdeced38 /mnt/Storage ext4 defaults 0 2
The very bottom entry is the second drive - '/mnt/Storage'. (the 2 at the end was a zero, I have changed it just now to be numbered as my boot drive to see if that made a difference.) This is mounted and started when I turn the system on and I can access it and use it as normal without issue, but in Firefox and any other program that allows saving to disk, I cannot set my download save location to this drive. If I go into a programs settings to try and select this as a save location, it is not listed. I'll put a screenshot of this in the comments. I dont know what other information to provide alongside this so Il leave it at this for now.