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Opened 6 months ago

Last modified 7 days ago

#2770 new defect

4.0.1 client connect to 4.0.1 server: transparent or black windows

Reported by: schvab Owned by: schvab
Priority: minor Milestone: 4.2
Component: client Version: 4.0.x
Keywords: Cc:


When on Kubuntu 18.04 I get blank (transparent, only frame and title visible) or black windows when connecting 4.0.1 client to 4.0.1 server. Same behavior when connecting locally or via SSL from different PC (with same OS).
If client is 3.0.9 (on Kubuntu) or 4.0.1 on Win7 x64 all works OK.

Attachments (3)

bugreport-xpra-200519.zip (437.9 KB) - added by schvab 6 months ago.
output form bug report tool
Screenshot_20200520_080512.png (35.3 KB) - added by schvab 5 months ago.
Screenshot_20200520_080625.png (211.6 KB) - added by schvab 5 months ago.

Download all attachments as: .zip

Change History (8)

Changed 6 months ago by schvab

Attachment: bugreport-xpra-200519.zip added

output form bug report tool

comment:1 Changed 5 months ago by Antoine Martin

Owner: changed from Antoine Martin to schvab

That's odd, maybe it's the selection of renderer that's causing problems.
Can you try:

  • toggling opengl on or off from the command line or system tray menu
  • trying different types of windows, ie: xterm and firefox

Does this make any difference?
If it's opengl related, you may want to try --opengl=force.

comment:2 Changed 5 months ago by schvab

when I run xpra attach ssl://schvab@schnuc.lan:14500/1 --ssl-server-verify-mode=none --speaker=enabled --microphone=disabled --min-quality=88 --opengl=force --title="@title@ schNUC"
the windows are see-through with only upper bar visible see 'Screenshot_20200520_080625.png'

when I switch off openGL (with openg=no and also in the tray menu) I get black windows see 'Screenshot_20200520_080512.png'

I try with firefox and xterm - in the 080625 its visible they behave the same.

Last edited 5 months ago by Antoine Martin (previous) (diff)

Changed 5 months ago by schvab

Changed 5 months ago by schvab

comment:3 Changed 5 months ago by Antoine Martin

From your screenshot, you seem to be connecting through a proxy server.
Have you tried connecting directly? (using a tunnel if needed)

Can you try connecting locally on the server and client? (with and without --mmap=off)

Does the problem go away if you use a different window manager? (metacity, fluxbox, or whatever)

comment:4 Changed 5 months ago by schvab

Priority: majorminor

I have new findings - the problem seems to be connected to the overall PC setup and openGL:

In the morning I had same behavior as seen on screenshots when connecting locally (on server, doing xpra attach :1) and when connecting over ssl with proxy from another PC but with same OS (kubuntu 18.04).
When I installed the 'another' PC to xubuntu 20.04 the remote ssl connection started working OK - windows were normal.
I updated the 18.04 server PC with all available updates but the behavior when connecting locally is still as seen on screenshots.
So when doing local connection (on server, doing xpra attach :1) also the mmap=off doesn't help and windows are still see-through.

It's probably worth to mention that both computers have Intel graphic accelerators.

I also tried today with third PC with kubuntu 18.04 and ati graphics as client and 4.0.1 worked fine.

P.S.: I get disconnected from ssl after random ~minutes, but that's different problem and I work around it by using ssh.

comment:5 Changed 7 days ago by Antoine Martin

Milestone: 4.2

As per comment:1 : toggling opengl on or off from the command line or system tray menu

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