Your system information

• Steam client version Jun 4 2020, at 05:51:01:
• Distribution: Mint 19.3
• Opted into Steam client beta?: No
• Have you checked for system updates?: Yes

Please describe your issue in as much detail as possible:

When the Steam client auto-updates, the hard drive will fill up with error logs. After the initial info (see below), the logs will repeat "type unknown not a basic type" over and over until the hard drive runs out of space. If I reboot the machine, then re-open Steam it will finish the update successfully and work fine until the next update. This has happened 3 times since I installed Steam a few months ago, so it is not specific to the latest version

(caja:2371): Gtk-CRITICAL **: 11:56:47.878: gtk_container_foreach: assertion 'GTK_IS_CONTAINER (container)' failed
Installing breakpad exception handler for appid(steam)/version(1586022601)
Installing breakpad exception handler for appid(steam)/version(1586022601)
Gtk-Message: 11:59:26.210: Failed to load module "gail"
Gtk-Message: 11:59:26.212: Failed to load module "atk-bridge"
Installing breakpad exception handler for appid(steam)/version(1586022601)
[0630/115926.762955:INFO:crash_reporting.cc(247)] Crash reporting enabled for process: browser
[0630/115926.816042:WARNING:crash_reporting.cc(286)] Failed to set crash key: UserID with value: 0
[0630/115926.816378:WARNING:crash_reporting.cc(286)] Failed to set crash key: BuildID with value: 1585960908
[0630/115926.816398:WARNING:crash_reporting.cc(286)] Failed to set crash key: SteamUniverse with value: Public
[0630/115926.816417:WARNING:crash_reporting.cc(286)] Failed to set crash key: Vendor with value: Valve
[0630/115926.994536:WARNING:crash_reporting.cc(286)] Failed to set crash key: UserID with value: 0
[0630/115926.994674:WARNING:crash_reporting.cc(286)] Failed to set crash key: BuildID with value: 1585960908
[0630/115926.994699:WARNING:crash_reporting.cc(286)] Failed to set crash key: SteamUniverse with value: Public
[0630/115926.994724:WARNING:crash_reporting.cc(286)] Failed to set crash key: Vendor with value: Valve
[0630/115926.995462:INFO:crash_reporting.cc(247)] Crash reporting enabled for process: gpu-process
Installing breakpad exception handler for appid(steam)/version(1586022601)
Installing breakpad exception handler for appid(steam)/version(1586022601)
Installing breakpad exception handler for appid(steam)/version(1586022601)
[0630/115927.197905:WARNING:crash_reporting.cc(286)] Failed to set crash key: UserID with value: 0
[0630/115927.198020:WARNING:crash_reporting.cc(286)] Failed to set crash key: BuildID with value: 1585960908
[0630/115927.198041:WARNING:crash_reporting.cc(286)] Failed to set crash key: SteamUniverse with value: Public
[0630/115927.198060:WARNING:crash_reporting.cc(286)] Failed to set crash key: Vendor with value: Valve
[0630/115927.199391:INFO:crash_reporting.cc(247)] Crash reporting enabled for process: utility
Installing breakpad exception handler for appid(steam)/version(1586022601)
Installing breakpad exception handler for appid(steam)/version(1586022601)
Installing breakpad exception handler for appid(steam)/version(1586022601)
CApplicationManagerPopulateThread took 24 milliseconds to initialize (will have waited on CAppInfoCacheReadFromDiskThread)
Installing breakpad exception handler for appid(steam)/version(1586022601)
Installing breakpad exception handler for appid(steam)/version(1586022601)
process 5718: Array or variant type requires that type signature be written, but string was written.
The overall signature expected here was 'll^C' and we are on byte 34 of that signature.
type unknown not a basic type
type unknown not a basic type

Steps for reproducing this issue:

1. Install Steam on Mint 19.3
2. Wait for an update to automatically install when launching Steam
3. Notice later on that day that my hard drive is out of space, delete the log file, restart my PC, then re-open Steam, now the update completes successfully.