I just found a solution to see the .SVG files in Thumbnails mode in xplorer2. There is a free plugin that allows Win Explorer (and xplorer2 as well) to preview the svg files: Windows® Thumbnail Plugin (650 KB)
Their comments: "The Windows File Explorer Plugin allows you to preview thumbnail images of your SVG Documents diretcly within the File Explorer.
System Requirements: Windows XP-Vista, 128 MB RAM,
Administrator Rights or Group-Policy for installing"
View SVG files in xplorer2
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