Bug 9873

Something weird is happening with the latest ark (18.12.1): there is no way to create a plain .tar file...

Steps to reproduce the issue:
1. Run ark from a konsole (to see the program output...)
2. Create a new archive (Ctrl+N or Archive-New)
3. In the "Create New Archive" window choose a suitable folder, an archive name (eg. test) and select "Tar" as archive Type.
4. OK
5. Now try to add some files: Alt+A or Archive-Add or "Add Files..." in the toolbar, then select a few files in the "Add Files - Ark" window and press the "Add" button.
6. Watch the error message "Could not set the compression method".

The output in konsole says: "ark.libarchive: Failed to set compression method: Using external zstd program"; and obviously no files get added to the temporary archive file...

When selecting a different archive type (I tried tar.gz and tar.xz...) the file adding works as expected and the "test.tar.gz/xz" archive gets created...

I did not try older releases of plasma5-ark, but I'm fairly sure that in the near past the .tar archive creation was working, so this is is easily also a very visible regression.

CCing Pulfer as the local KDE guy...