pcmanfm suddenly froze when opening a folder

[Martin Constantino–Bodin]

Nothing complex here: I just opened pcmanfm from the usual interface and opened a folder. This folder was accessible from the terminal before and after launching pcmanfm so there was no reason for it to crash. This folder was in the same disk as the operating system, so nothing funny here. And yet pcmanfm suddenly froze: its window was no longer redrawing parts that have been hidden by another window, but the desktop (which is operated by pcmanfm) lost all its icons. I’m sorry to say that there was no reason for it to crash at this moment: no usb-device connected, no remote folder, just a plain folder in the home folder. I haven’t changed this folder for at least a week, and yesterday, pcmanfm was able to access it just fine. I opened a terminal and typed “apport-bug pcmanfm” while its window was still opened, then killed it once the report was sent.

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: pcmanfm 1.2.5-3ubuntu1
ProcVersionSignature: Ubuntu 4.15.0-46.49-generic 4.15.18
Uname: Linux 4.15.0-46-generic x86_64
ApportVersion: 2.20.9-0ubuntu7.6
Architecture: amd64
Config_pcmanfm_System_Lubuntu: Error: [Errno 2] Aucun fichier ou dossier de ce type: '/etc/xdg/pcmanfm/Lubuntu/lubuntu.conf'
CurrentDesktop: LXDE
Date: Thu Mar 28 22:30:30 2019
InstallationDate: Installed on 2016-12-05 (843 days ago)
InstallationMedia: Lubuntu 16.10 "Yakkety Yak" - Release amd64 (20161012.1)
SourcePackage: pcmanfm
Udisks_dump: Error: [Errno 2] Aucun fichier ou dossier de ce type: 'udisks': 'udisks'
UpgradeStatus: Upgraded to bionic on 2018-08-29 (211 days ago)

[Martin Constantino–Bodin (martin-bodin)]

This is possibly unrelated, but I just realised that apport-bug printed out some errors during the report. I’m putting them here in case it out help.

$ apport-bug pcmanfm
[9845:9845:0328/223211.975496:ERROR:sandbox_linux.cc(364)] InitializeSandbox() called with multiple threads in process gpu-process.
[9806:9806:0328/224247.534916:ERROR:event_router.cc(741)] Event dispatched while shutting down extensions browser client.
[9806:9806:0328/224247.534994:ERROR:event_router.cc(741)] Event dispatched while shutting down extensions browser client.
[9806:9806:0328/224247.636013:ERROR:http_bridge.cc(126)] Not implemented reached in virtual void syncer::HttpBridgeFactory::OnSignalReceived()

[Martin Constantino–Bodin (martin-bodin)]

Oh, and I forgot to mention: after killing pcmanfm as the system suggested, I could restart pcmanfm without issue. The desktop was still unusable for this session, but pcmanfm’s windows worked well after restarting it, without the need of restarting the session. So I guess that this is a minor issue.

[Martin Constantino–Bodin (martin-bodin)]

This bug is more frequent than what I initially expected: it’s the third time it occurred since I initially reported. Has something been changed recently in the software or its dependencies?