After further testing of the issue that occurs in Chrome, it seems like a bug in the RadFileExplorer. I have logged it into our DataBase for further investigation.
For the time being, to avoid this problem I can suggest you to limit the maximum number of upload fields, e.g.:
RadFileExplorer1.Upload.MaxFileInputsCount = 5;
As a small token of gratitude for your contribution I have updated your Telerik points.
the Telerik team
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