Update: I downgraded insync to 1.4.9, having downloaded the .deb from links here.
Looks like I will keep it at hand while 1.5.1 startup issue is being studied.
Also: version 1.5.1., when run as “insync start --no-daemon” prints:
NFO 2018-09-13 20:33:01,777 [__main__insync__:main:98] insync version: 1.5.1.37343
INFO 2018-09-13 20:33:01,778 [__main__insync__:main:99] client created <ideskmain.client.Client object at 0x7f9165083b90>
INFO 2018-09-13 20:33:01,778 [unix_socket_server_portable:start:49] unix socket server thread start
INFO 2018-09-13 20:33:01,779 [__main__insync__:main:107] starting client
INFO 2018-09-13 20:33:01,782 [fswatch:_start:532] LinuxFSWatcher._start
INFO 2018-09-13 20:33:01,783 [fswatch:_pull_loop:267] Inotify loop enter
libpng warning: iCCP: known incorrect sRGB profile
[0913/203301.811310:WARNING:stack_trace_posix.cc(699)] Failed to open file: /tmp/.glj5KiHk (deleted)
Error: No such file or directory
INFO 2018-09-13 20:33:01,979 [gdsyncer:sync_account:153] Syncing GDUser(id=u'111494326092827652999', email=u'[email removed]', name=u'[name removed]').
libGL error: No matching fbConfigs or visuals found
libGL error: failed to load driver: swrast
Received signal 11 SEGV_MAPERR 0000000001c5
#0 0x7f916ad8c95f <unknown>
#1 0x7f91697be85d <unknown>
#2 0x7f916ad8ce6e <unknown>
#3 0x7f91a85f0390 <unknown>
#4 0x7f91345a5321 <unknown>
#5 0x7f9169820949 <unknown>
#6 0x7f916980b9a8 <unknown>
#7 0x7f916b8c8add <unknown>
#8 0x7f9169b0f411 <unknown>
#9 0x7f9169b10c05 <unknown>
#10 0x7f916bd7eea7 <unknown>
#11 0x7f916d5b5c65 <unknown>
#12 0x7f916adf5315 <unknown>
#13 0x7f916adf06b0 <unknown>
#14 0x7f91a85e66ba start_thread
#15 0x7f91a79f241d clone
r8: 0000000000000000 r9: 0000000000000000 r10: 00000000000000e9 r11: 0000000000000000
r12: 000000000000010d r13: 000000000000000a r14: 000000000000009a r15: 000000000000000a
di: 00000000030499c4 si: 0000000000000001 bp: 00007f91357f9590 bx: 0000000003041bb0
dx: 0000000000000019 ax: 00000000030499b0 cx: 0000000000000001 sp: 00007f91357f9530
ip: 00007f91345a5321 efl: 0000000000010206 cgf: 002b000000000033 erf: 0000000000000004
trp: 000000000000000e msk: 0000000000000000 cr2: 00000000000001c5
[end of stack trace]
Calling _exit(1). Core file will not be generated.