Certainly better than allowing it, but doesn't this break the use case of #2599?
1. Open a document 2. File->Save As 3. Notice an interesting file in the list of files in the dialog 4. Open interesting file from the command-line (in another program) with geany interesting-file. The file does not open (because the dialog is still open). 5. User says WHAT THE!!!! 6. complete save as 7. file opens 8. User says WHAT THE!!!!