$  dmesg | tail
[ 6078.209449]  sdb:
[ 6078.521239] FAT-fs (sdb): Volume was not properly unmounted. Some data may be corrupt. Please run fsck.
[ 6080.180670] sd 1:0:0:1: [sdc] 7954432 512-byte logical blocks: (4.07 GB/3.79 GiB)
[ 6080.185922] sd 1:0:0:1: [sdc] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA
[ 6080.198020]  sdc: sdc1
[ 6080.841029] FAT-fs (sdc1): Volume was not properly unmounted. Some data may be corrupt. Please run fsck.
[ 6108.259519] FAT-fs (sdc1): error, corrupted directory (invalid entries)
[ 6108.259526] FAT-fs (sdc1): Filesystem has been set read-only
[ 6108.945912] FAT-fs (sdc1): error, corrupted directory (invalid entries)
[ 6194.304105] epiphany-search[5187]: segfault at 5 ip 00007ff8b0ed3e30 sp 00007ffef76a1740 error 6 in libwayland-server.so.0.1.0[7ff8b0ec8000+10000]