Disable source code view of .eml attachments

[cm-schl]

At the moment SnappyMail when showing an email with an .eml attachment offers two options to the user:

When the user clicks on section (1) the source code of the attachment is shown, instead when clicking on (2) the eml preview window is opened.

Describe the solution you'd like
As the source code view is not really useful for "normal" users I would like to ask to change the behavior that clicking on (1) should open the preview window (what is opened at the moment when clicking on (2)) and clicking on section (2) should give the option to download / open the .eml with a local program.

Ideally the cursor should also change when hoovering over the filename - at the moment the normal mouse pointer is shown and it isn't clear that a click on the filename also triggers some action.