Really useful for learning purposes. Thanks a lot.

Brett

Using the –disable-gpu-sandbox command line parameter fixes the issue: previewing a scene in Chrome works without any apparent issues (as before).

Thanks,

Brett

I'll try with the –disable-gpu-sandbox flag as suggested: https://bugs.chromium.org/p/chromium/issues/detail?id=615651#c7

Either way, I'll let you know.

Uncaught engine panic:
The engine tried to perform an invalid operation and halted.

B4W WARN: Canvas size exceeds platform limits, downscaling
================================================
Blend4Web CE version 16.06 - Ubuntu 16.04
Chromium Version 50.0.2661.102 Ubuntu 16.04 (64-bit)

GL_VENDOR NVIDIA Corporation
GL_RENDERER GeForce GT 720M/PCIe/SSE2
GL_VERSION 4.4.0 NVIDIA 340.96

================================================
BROWSER CONSOLE OUTPUT

GL_INVALID_OPERATION : glGenSyncTokenCHROMIUM: fence sync must be flushed before generating sync token
viewer.html:1 WebGL: CONTEXT_LOST_WEBGL: loseContext: context lost
print.js:74 B4W ERROR: WebGL context losterror @ print.js:74
print.js:112 B4W WARN: Canvas size exceeds platform limits, downscaling
print.js:74 B4W ERROR: No aspect ratioerror @ print.js:74
util.js:2104 Uncaught engine panic:
The engine tried to perform an invalid operation and halted.
Please copy the console contents above and submit it to the Blend4Web forum at
https://www.blend4web.com/en/forums/forum/17/
print.js:112 B4W WARN: Canvas size exceeds platform limits, downscaling
print.js:74 B4W ERROR: No aspect ratioerror @ print.js:74
util.js:2104 Uncaught engine panic:
The engine tried to perform an invalid operation and halted.
Please copy the console contents above and submit it to the Blend4Web forum at
https://www.blend4web.com/en/forums/forum/17/

================================================
BASH CONSOLE OUTPUT

Read new prefs: /home/brettk/.config/blender/2.77/config/userpref.blend
found bundled python: /home/brettk/Tools/blender-2.77a/2.77/python
serving at port 6687
Scene saved to /home/brettk/Tools/blend4web_sdk_16.06/tmp/preview/preview.json
EXPORT OK
Created new window in existing browser session.
Scene saved to /home/brettk/Tools/blend4web_sdk_16.06/tmp/preview/preview.json
EXPORT OK
Created new window in existing browser session.
Created new window in existing browser session.
WARNING:tornado.access:404 GET /index_assets/favicon.ico (::1) 0.79ms
WARNING:tornado.access:404 GET /favicon.ico (::1) 0.80ms
[7992:8058:0630/194652:ERROR:gcm_store_impl.cc(306)] Failed to open database /home/brettk/.config/chromium/Default/GCM Store: Invalid argument: /home/brettk/.config/chromium/Default/GCM Store: does not exist (create_if_missing is false)
[7992:8058:0630/194652:ERROR:gcm_store_impl.cc(306)] Failed to open database /home/brettk/.config/chromium/Default/GCM Store: Invalid argument: /home/brettk/.config/chromium/Default/GCM Store: does not exist (create_if_missing is false)
WARNING:tornado.access:404 GET /index_assets/favicon.ico (::1) 1.00ms
WARNING:tornado.access:404 GET /favicon.ico (::1) 0.82ms
Scene saved to /home/brettk/Tools/blend4web_sdk_16.06/tmp/preview/preview.json
EXPORT OK
Created new window in existing browser session.
../../sandbox/linux/seccomp-bpf-helpers/sigsys_handlers.cc:**CRASHING**:seccomp-bpf failure in syscall 0099
Received signal 11 SEGV_MAPERR 000002c20063
#0 0x7f929aaa639e base::debug::StackTrace::StackTrace()
#1 0x7f929aaa678b <unknown>
#2 0x7f928463b3d0 <unknown>
#3 0x7f928ddb0453 sandbox::CrashSIGSYS_Handler()
#4 0x7f928dfc1697 sandbox::Trap::SigSys()
#5 0x7f928463b3d0 <unknown>
#6 0x7f9284368487 sysinfo
#7 0x7f928436642e get_phys_pages
#8 0x7f928432ea60 __sysconf
#9 0x7f928429a6ae qsort_r
#10 0x7f9273ae03bb <unknown>
#11 0x7f9273ae667a <unknown>
#12 0x7f9273be6208 <unknown>
#13 0x7f9273db5bc9 <unknown>
#14 0x7f9273dc9db7 <unknown>
#15 0x7f927433750b <unknown>
#16 0x7f9274339c6e <unknown>
#17 0x7f92744cb176 <unknown>
#18 0x7f92744ceab2 <unknown>
#19 0x7f92743711e5 <unknown>
#20 0x7f9274371562 <unknown>
#21 0x7f92743715f8 <unknown>
#22 0x7f92744cb796 <unknown>
#23 0x7f92744d81d4 <unknown>
#24 0x7f927407c876 <unknown>
#25 0x7f927407cbf8 <unknown>
#26 0x7f927407ce28 <unknown>
#27 0x7f92744ddde3 <unknown>
#28 0x7f9273ff3da1 <unknown>
#29 0x7f9292c58f51 <unknown>
#30 0x7f9292c597bc <unknown>
#31 0x7f9292c59867 <unknown>
#32 0x7f9292c5a012 <unknown>
#33 0x7f9292c5a1ed <unknown>
#34 0x7f9292c74da2 <unknown>
#35 0x7f9292c27b3a gpu::CommandParser::ProcessCommands()
#36 0x7f9292c89b9a gpu::GpuScheduler::PutChanged()
#37 0x7f929670e58e <unknown>
#38 0x7f9296713370 <unknown>
#39 0x7f9292029437 IPC::MessageRouter::RouteMessage()
#40 0x7f929670c0a5 content::GpuChannel::HandleMessageHelper()
#41 0x7f929670c14e content::GpuChannel::HandleMessage()
#42 0x7f929670a28c <unknown>
#43 0x7f929aaa7fb9 base::debug::TaskAnnotator::RunTask()
#44 0x7f929aaca51c base::MessageLoop::RunTask()
#45 0x7f929aacad0d base::MessageLoop::DeferOrRunPendingTask()
#46 0x7f929aacafd9 base::MessageLoop::DoWork()
#47 0x7f929aa96f19 base::MessagePumpGlib::HandleDispatch()
#48 0x7f929aa96f5d <unknown>
#49 0x7f92865bb1a7 g_main_context_dispatch
#50 0x7f92865bb400 <unknown>
#51 0x7f92865bb4ac g_main_context_iteration
#52 0x7f929aa96c6a base::MessagePumpGlib::Run()
#53 0x7f929aae7298 base::RunLoop::Run()
#54 0x7f929aac9745 base::MessageLoop::Run()
#55 0x7f929674167f <unknown>
#56 0x7f929620f1c4 <unknown>
#57 0x7f929620e5f1 content::ContentMain()
#58 0x560c1888529a <unknown>
#59 0x7f9284281830 __libc_start_main
#60 0x560c18885159 <unknown>
r8: 00007ffd4225007c r9: 0000000000000001 r10: 0000178dc7e98820 r11: 0000000000000000
r12: 00007ffd42250080 r13: 0000178dc23ed400 r14: 00007ffd422500c0 r15: 0000178dc3171d80
di: 0000000000000001 si: 00007f928ddb3079 bp: 00007ffd422500c0 bx: 0000000002c20063
dx: 0000000000020000 ax: 0000000002c20000 cx: 00007f928463a4fd sp: 00007ffd42250080
ip: 00007f928ddb0453 efl: 0000000000010206 cgf: 0000000000000033 erf: 0000000000000006
trp: 000000000000000e msk: 0000000000000000 cr2: 0000000002c20063
[end of stack trace]
[7992:7992:0630/194706:ERROR:gpu_process_transport_factory.cc(655)] Lost UI shared context.