Lane lenght jumps to the far end

I am using version 4.0.01 on linux (4.19.0-2-amd64) and Windows (win32 (6.1) x86_64).
I have created a BPMN Process design diagram having two lanes.
At a certain point, which I cannot reproduce, any attempt of resizing the length of the lanes randomly put the lane length to the far end of the canvas.
By resizing little by little I managed to put back the lane length close to the extent of the content. Nevertheless, if I save the diagram in a file, the image has the size of the (big) canvas instead of that of the lane. I have to resize it with a graphic editor (crop to the content).

Hi,

Same problem here. I didn't find any way to resize the lanes.
In my case the diagram used to be much bigger but has been simplified. Lanes length may have kept their bigger length.

Version 4.1.00
Build Id : 202009292130
Système : win32 (10.0)
Architecture : x86_64