In the edit screen for the "Folder" resource, in the "Content" section, it is possible to rename a (sub)folder to have a name that begins with, or ends in, a dot (.). However, when changing to this subfolder afterwards, the folder appears empty. See test instructions for details.

Note that this problem appears for folder names like "test." and ".test" but not for "test.test" .

Replication instructions:

• Go to a Moodle course page, and turn editing on.
• Click "Add a resource... Folder".
• Go to the "content" section, click "Create Folder", type the name: "test", then click "OK".
• Click on the folder name "test", and add a file to this folder.
• Return to the main directory (click "Files").
• Right-click on the "test" folder and choose "Rename".
• As the new name, type "test." (note trailing dot), then click "OK".
• Click on the folder "test." to open it.

EXPECTED BEHAVIOUR: Title lines says "Path: Files > test.", contents of the folder are being displayed.
ACTUAL BEHAVIOUR: Title line says "Path: Files > test", folder appears empty ("No files attached").