lags when zooming to the minimum value

[RdEErAqUa]

I use ubuntu 20.04. When i zoom to the minimun value(I choose in the settings, it can be 50 - 75 .. )  then the whole system starts to slow down. this happens only at the minimum zoom and only under certain conditions: background video playback. At the same time, the FPS counter does not show the FPS subsidence, and the system just starts micro-freezes. I thought that something was wrong with my system, but due to the fact that this happens only at the minimum zoom and an excellent smooth picture at the other zooms, I suspect that this may be a bug.