File - export as PDF - writes SVG file instead

[tobiastesteron]

Brief summary of issue

File - export as PDF - writes SVG file instead. The file generated has extension .pdf but is of mimetype "image/svg+xml"

Steps to reproduce the issue

1. Take any screenshot
2. Shutter - Menu "File" Topic "export as pdf"
3. Store file (e.g. in tmp)
4. Open the file with evince - throws an error that mimetiype is not supported

Error output

6. file --mime-type "yourfile".pdf yourfile.pdf: image/svg+xml

Extra information, such as Shutter version, display server in use (Xorg or Wayland), operating system and ideas for how to solve:

0.99.6 (latest), OS is LMDE6.
Probably the save-methode has mixed up the file type.
Former versions did not have this issue.

[Photon89]

Thanks for reporting, should be fixed in #789!