Hi! I do not understand what you mean when you reference "scans", but I will assume you are talking about a certain filetype (like PDF or JPEG). "Firefox files", I assume, are files that open in Firefox when opened without a precedent. To change what app is used when opening a specific type of file, under File Explorer, Right-Click a file you want to open (in this case, your "Firefox files"), hit Open With > Choose another app (even if the app you want is already listed). Find the app you wish to open the filetype with, and ensure "Always use this app to open [placeholder] files" is checked. The issue should now be solved. Alternatively, go to Settings > Default Apps, and change default apps for filetypes of your volition. Let me know if I have assumed incorrectly! Cheers,