Usually in the cistern of the toilet in an actuator of a shutoff valve on the lever set hollow plastic float. If its integrity is violated, it fills with water and stops working. As a consequence, continuous noise of flowing water, condensed moisture on the tank, dampness and mold.
Radically and just to correct the situation will help a stick of foam, which you must impose on the lever instead of the float.
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“NEPROLIVAJKU” FOR PAINT
The simplest "neprolivajku" for the paint or varnish can be done EA literally two minutes, if you drive in a Board cut two nails and pull them rubber ring cut from a Bicycle or a car camera.