Fixed Issues since Linux Mint 19 BETA

All editions
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artwork:
    mint-x:
        no icons in Online accounts > Information about Gnome online accounts -> Gnome Contacts, Gnome Documents, Gnome Maps and Gnome Photos
    mint-y:
        thunderbird icon isn't the same as its flatpak
        in nemo additional pane, select a folder in the left page, click in the right pane. The selected folder in the left pane is white on grey, almost invisible.
        video and subtitle icons are too similar

The fortune command says 'no fortunes found' -> leftover, fortune is now removed.
gdebi doesn't install packages unless it's run from the terminal

Cinnamon Edition
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    goa: ubuntu SSO isn't functional -> it won't work without snapd, and it's useless for anything else. Ubuntu non-gnome users auth in snapd CLI anyway, so this should be removed. We don't need it, it's not necessary and it won't work OOTB.

MATE Edition
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Xfce Edition
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