System lockup when opening Scatter 11 sometimes

[acoutts]

• Ubuntu 18.04
• Linux 4.15.0-50-generic
• Scatter Desktop v11.0.0

I've been chasing this intermittent issue down for some time now.

Everything will be working great. Then suddenly web apps won't be able to detect scatter even though it's still open as it was before.

• Browser console says the local.get-scatter.com connection failed as it tries each time.
• I close Scatter desktop and try to re-open it.
• Upon re-opening, the entire system is locked.
• The scatter window never appears.
• Mouse continues to work, but unable to click on anything.
• Alt-tab doesn't work, keyboard doesn't seem to respond to any open windows.
• Only course of action is to ctrl + alt + F4 to another session and restart lightdm: sudo service lightdm restart

While looking at syslog after the fact I found some messages from Scatter Desktop moments before the lockup:

Jun 27 06:41:33 xff0c appimagekit-scatter.desktop[1045]: [xcb] Unknown sequence number while processing queue
Jun 27 06:41:33 xff0c appimagekit-scatter.desktop[1045]: [xcb] Most likely this is a multi-threaded client and XInitThreads has not been called
Jun 27 06:41:33 xff0c appimagekit-scatter.desktop[1045]: [xcb] Aborting, sorry about that.
Jun 27 06:41:33 xff0c appimagekit-scatter.desktop[1045]: scatter: ../../src/xcb_io.c:259: poll_for_event: Assertion `!xcb_xlib_threads_sequence_lost' failed.

Unsure exactly if this is the cause, but documenting for others to see if I'm alone.

[nsjames]

I wonder if it's getting locked trying to locate ports. I just heard of another similar issue with someone also on ubuntu. I'll have to dig deeper into this one.

[sgehrman]

I have the same issue. Randomly freezes my Linux machine. I have to reboot to get back up.

I recommend updating all your npm package and posting a new build. Maybe something was fixed in one of your packages.

[nsjames]

@sgehrman this actually already happened on the core-extrapolation branch which will be merged into 11.1.0 for next release

I'd say you could try that version but it's going to be very hard since there's localized npm modules there which aren't on npmjs yet. Might want to wait for next release to see if it fixes the issue.

[acoutts]

This seems to still be happening in 11.01, have to downgrade to 10.x in order to avoid system lockups again.

[educatedwarrior]

Same issue here. looking forward to fix. How can an app crash the entire OS.. wierd, and I thought Linux was bulletproof.

[sgehrman]

waiting for a fix

[nsjames]

Does this still happen on Scatter 12?

[educatedwarrior]

Since Scatter 12, I have not had an issue with locking up in Ubuntu/Linux Mint... thanks for fixing that.