open screen with some graphs, choose period other than one hour. click on some graph - notice how it opens 1 hour graph not the period screen was displaying (assuming that graph had not some other period selected before)

regression, broken by :

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r30977 | eduards | 2012-10-19 15:49:58 +0300 (Fri, 19 Oct 2012) | 1 line

..F....... ZBXNEXT-1398 implemented flickerfree screen shadowing for old screen data