Your system information

• Steam client version (build number or date): version 1500335472
• Distribution (e.g. Ubuntu): Ubuntu 16.04.2 LTS
• Opted into Steam client beta?: [Yes/No] N
• Have you checked for system updates?: [Yes/No] Y

Please describe your issue in as much detail as possible:

Seeing this issue. Running steam on Unbuntu Distro on Paperspace.

AMD64 processor
threadtools.cpp (1343) : Assertion Failed: Thread synchronization object is unuseable

Steps for reproducing this issue:

1. run steam command
2. Triggers x forwarding
3. x forwarding freezes when asing me to log in. The UI is unresponsive and eventually the terminal crashes

similiar to #5101

Full ouput

Running Steam on ubuntu 16.04 64-bit
STEAM_RUNTIME is enabled automatically
[2017-08-06 01:22:47] Startup - updater built Jul 17 2017 23:10:02
Looks like steam didn't shutdown cleanly, scheduling immediate update check
[2017-08-06 01:22:49] Checking for update on startup
[2017-08-06 01:22:49] Checking for available updates...
[2017-08-06 01:22:49] Download skipped: /client/steam_client_ubuntu12 version 1500335472, installed version 1500335472
[2017-08-06 01:22:49] Nothing to do
[2017-08-06 01:22:49] Verifying installation...
[2017-08-06 01:22:49] Performing checksum verification of executable files
[2017-08-06 01:22:50] Verification complete
threadtools.cpp (1343) : Assertion Failed: Thread synchronization object is unuseable