I have installed Natron in my desktop Linux MInt 20.3 using the flatpak from flathub version 2.4.3, and the problem is that everyting looks perfect except my timeline.

I have sent a picture to show how it looks.

I have tried to restart the pc, to rezise the window, to go full screen, to chane the display ratios, and the problem is still there.

Hope to get it fixed.