One day I noticed that the cursor was moving very slowly in the browser on the LG 43UK630PBL TV.
The problem with the slow cursor was only in the browser, there were no problems in other applications, well, there is no cursor there, switching between objects was done well.
It turned out that the problem was in the dead batteries. When I measured the voltage of the batteries with a tester, one had 1.08 V and the other 1.00 V. After replacing them with new ones, the problem disappeared.