While viewing an album, attempting to export the cover for the album from the edit pane on the left brings up a Save As dialog where the file type is .*. Previously, this defaulted the file extension to either .png or .jpg. I noticed this with 2.95 and was not present in 2.94. If you want to export the cover, you need to know the file type of the cover as you must specify for example, folder.jpg or folder.png in the Save As Dialog.
Interestingly enough, no, it does not show image/jpeg. So, therefore I understand you don't know what extension to apply.
So, as an enhancement, does it make sense to add both PNG and JPG extensions to the save-as dialog so user can simply select the type to build the filename vs having to type the full extension?
The reason I ask for this is once MP3Tag writes the file named "folder.", it shows up in Windows 7 explorer as "folder." This file cannot be deleted from Windows explorer and can only be deleted using a Command Prompt and specifying del "folder.*" to accomplish the file removal.
Thanks for reporting. I've added extended means with Mp3tag v2.95a to detect the image format based on the actual data for covers where no mimetype is set.