The customizable workspace UI of Dragonfly takes into account the user's settings and state. Sometimes the user state could be corrupted for unexpected reasons and a panel in the workspace may not show up. 

As an example, if the Image Processing panel doesn't show up, you can try the following steps to restore it:

- close Dragonfly;
- open a file explorer to %localappdata% \ORS\Dragonfly2020.1;
- just for precaution, do a backup of the file "StateData.xml" (in case something went wrong after the changes);
- open the file StateData.xml with a text editor;
- in the file StateData.xml, search for "ImageProcessingWidgetDispositions". There should be exactly one occurrence;
- erase the node associated to the key "ImageProcessingWidgetDispositions" (all the text <Entry Key=" ImageProcessingWidgetDispositions " [...] />);
- save and close the file;
- restart Dragonfly.