Search bar Chrome/Chromium Youtube is freezing

for long time I have problem with searching on Youtube website. Search bar is freezing / works really slowly. When I type something for first time (after opening newtab of browser) everything is good, but when I search something after playing some song for example, than is really difficult delete and write new search into search bar. Its takes long time ( cca 20s or more).
I use two PC, both with oS 15.1, first with Chrome and second with Chromium. Problem is with both PC/browsers.

This problem is since 42.3.
Cold you help me, please?

I noticed, that when this happening, one thread of CPU is 100% using. I have 8 thread CPU. The rest thread is almost idle.