I made a smoke simulation, and wanted to deactivate the "Use Flow" property of the flow object during the animation to stop smoke generation.
So I select frame 90, add a keyframe by clicking on the dot on the right of the "Use Flow" property while it is checked. Then I go to frame 91, uncheck "Use Flow" and add a new keyframe the same way. That way, it generates smoke and at frame 91, it stops.
Problem is, it doesn't. Actually if I click on any other frame, "Use Flow" is checked, even when I select frame 91 again.
I did the same thing in another file and it works perfectly. I don't get it, is it a bug ?