An additional button should be added when right-clicking a sample or folder containing samples in the "My Samples" browser, allowing users to open the file or folder's location in their system's file browser.
This makes it easy to locate sample files on your system from within LMMS if you need to edit, delete, rename, or otherwise modify your samples.
This screenshot is from FL Studio, but displays the functionality.


Most helpful comment
5454 implements a first solution which opens the folder that contains the selected file. It looks like this: