Finally found root of problem. In game\modules\0005_core\screens\image_hook.rpy MaxableImage render function calls renpy.redraw which recursively calls MaxableImage.render. Tried to move renpy.redraw into event function like shown in documentation example:
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but it didn't worked - images stopped react on clicks. So I restricted renpy.redraw to be called only once inside render function and added per_interact function which calls render function. Totally don't understand why it works, but it works. Tested old save and new game - images work as before and cpu is calm.
View attachment 4056576