I recently upgraded libcurl in Testing repos, which upgraded libgnutils-deb0-28 v3.3.15-2 to v3.3.15-5, which BROKE Feh and GIMP (both will"segfault" upon startup). Luckily I had another box which had not been upgraded which still worked as I did upgrades one-by-one to find the culpret. Turns out it was this. I downgraded using Debian's"Snapshot" site back to v3.3.15-2, which fixed both, and pinned.