Browse by Thumbnail (Windows)

[Gimphried]

Hello Gimposaurus 

Gimp 2.10.28 File > Open dialog box has a Preview window to display the thumbnail of the selected picture before you can open it or not.

On the other hand, in Gimp 2.10.28, the keyboard shortcut Ctrl+B opens the Toolbox window showing the Wilber's eyes of the Gimp's mascot above the tools.
In Windows 10, you can play with the Windows key + arrow on the bottom of the keyboard to organize your working environment:

• Gimp on the left side of your screen or on the left dual-screen;
  
• Windows File Explorer on the right, side-by-side with Gimp.
  

or the opposite if you do not wish to cross the treeview of folders during the drag and drop.

In the Windows 10 File Explorer, you can preview thumbnail of the pictures in any folder by the menu View > Large icons.
Finally, you can drag a picture from the Windows File Explorer to the Wilber's eyes in Gimp:

• Directly in the Gimp editor if there is not yet any loaded picture. Wilber appears at the bottom of the editor;
  
• In the Toolbox Window, above the tools, where you can find the Wilber's icon, target of the drop.
  

Regards.