nautilus doesn't display thumbnails on network share

[Tessa]

I've got nautilus configured to display thumbnails on network shares (prefs -> search&preview -> thumbnails -> all files), but in 20.04 it never shows thumbnails on my samba network shares. Not sure what broke since previous ubuntu releases, but it's definitely not working now. local thumbnail generation and display works fine still, so there isn't an issue with the thumbnail generation itself as far as I can tell.

ProblemType: Bug
DistroRelease: Ubuntu 20.04
Package: nautilus 1:3.36.3-0ubuntu1
ProcVersionSignature: Ubuntu 5.4.0-47.51-lowlatency 5.4.55
Uname: Linux 5.4.0-47-lowlatency x86_64
NonfreeKernelModules: zfs zunicode zavl icp zcommon znvpair nvidia_modeset nvidia
ApportVersion: 2.20.11-0ubuntu27.8
Architecture: amd64
CasperMD5CheckResult: skip
CurrentDesktop: ubuntu:GNOME
Date: Thu Sep 17 17:22:15 2020
InstallationDate: Installed on 2020-07-15 (64 days ago)
InstallationMedia: Ubuntu 20.04 LTS "Focal Fossa" - Release amd64 (20200423)
SourcePackage: nautilus
UpgradeStatus: No upgrade log present (probably fresh install)
usr_lib_nautilus:

[Tessa (unit3)]

as an update, this is still broken on 20.10. as well, I've noticed an interesting detail, which is that thumbnailing *is* working on my connected Google Drive. so it really does just seem to be samba shares.

As well, I've discovered that if I remove the `/home/tessa/.cache/thumbnails/fail/gnome-thumbnail-factory` directory, then when I reload a samba dir with images in it in nautilus, and creates a bunch of PNGs in it for the number of thumbnails it's failed to generate from the network share, and all id by file as "PNG image data, 1 x 1, 8-bit/color RGBA, non-interlaced". So it's definitely trying to create the thumbnails, and then failing in some way.

is there any feedback on how to debug this further and find out why it's failing? is there a way to get nautilus to log what it's doing here for further inspection?

[Sebastien Bacher (seb128)]

Thank you for your bug report, you might want to report it upstream as well on https://gitlab.gnome.org/GNOME/nautilus/-/issues

Is there any output in the journalctl log when thumbnails fail? what's the format of the images and their naming? (remote views rely on the filename rather than poking at the content)

[Tessa (unit3)]

Unfortunately, nothing shows up in journalctl. Is that where nautilus normally logs things? The images have all kinds of names, since they all fail, but consistently I see failures on very basic names like "icon.png" or "2020-01-01_365243.jpeg" or similar.

[Tessa (unit3)]

Interestingly, I just noticed in the man page that nautilus has a self-check function. when I run `nautlius -c` and then look at journalctl, I see the following. not sure what it means, but nautilus thinks there's a problem:

Nov 23 02:18:45 boxxy org.gnome.Nautilus[1125330]: running nautilus_self_check_file_utilities
Nov 23 02:18:45 boxxy org.gnome.Nautilus[1125330]: running nautilus_self_check_file_operations
Nov 23 02:18:45 boxxy org.gnome.Nautilus[1125330]: running nautilus_self_check_directory
Nov 23 02:18:45 boxxy org.gnome.Nautilus[1125330]: FAIL: check failed in ../src/nautilus-directory.c, line 1987
Nov 23 02:18:45 boxxy org.gnome.Nautilus[1125330]: evaluated: g_hash_table_size (directories)
Nov 23 02:18:45 boxxy org.gnome.Nautilus[1125330]: expected: 1
Nov 23 02:18:45 boxxy org.gnome.Nautilus[1125330]: got: 8

[Tessa (unit3)]

and per your suggestion, here's the upstream bug I just filed:
https://gitlab.gnome.org/GNOME/nautilus/-/issues/1678

[Sebastien Bacher (seb128)]

thanks!