Hi everybody,
At first, here is my setup:
Ubuntu 18.04.4 LTS (system up to date)
8Gb RAM
Intel(R) Core(TM) i5 CPU 760 @ 2.80GHz
NVIDIA Corporation GT215 [GeForce GT 240] ( Drivers : 340.108 )

kdenlive-19.12.2c-x86_64.appimage

I have big issue when using v19 (issue not present in V18): the content of clip and project monitor are always flickering.
The only way I found to use monitor without that, is to use in fullscreen mode (Monitor/switch monitor fullscreen)

I've tried multiple format files (from low quality to high, videos or pictures, etc...)
I've also tried to use my system in dual/single screen

No cpu, error message in my logs
Proxy clips are (of course enabled)

I can also reproduce the problem with a project that contains only an empty Title clip
Problem not present in last V18 (kdenlive-18.12.1b-x86_64.appimage), but appears in first V19 (kdenlive-19.04.0-x86_64.AppImage)

Any ideas?
Thank you so much to the kdenlive dev community which provide us a very smart piece of code.

maybe something related to back-end open GL ? ( SETTINGS --> OPENGL BACKEND )

Hi bartoloni,

bartoloni wrote:maybe something related to back-end open GL ? ( SETTINGS --> OPENGL BACKEND )

I don't have any OPENGL or Backend related option in all the settings.

I just fixed my problem by changing the video drivers to "nouveau"

the below thread gave me this hint:
https://www.mail-archive.com/search?l=k ... newest&f=1

Hello,

I have the same issue.
If I change the video drivers to "nouveau", I have a poor ubuntu resolution (640*480 only...) so it's not a solution for me.
I use Ubuntu 20.04 with latest Nvidia drivers 340.108.
Graphic card is (old) GeForce 210.

Any help appreciated...