This issue pertains to the Telerik Testing Framework.
This is expected behavior. All browsers must be at 100% zoom level for test execution to perform correctly. Although targeted at a recording issue in Test Studio, the resolution in this article outlines the needed settings.
Silverlight and WPF applications do not allow the injection of click, select, and set text events directly into the DOM. The Framework has to simulate system wide mouse moves, clicks, and key presses instead. The browser must be at 100% default zoom level for these actions to perform correctly.
the Telerik team
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