Digikam 4.14.0 -> 5.3.0 - big update, some questions

[Jens Benecke]

Hello all,

I am trying to upgrade to Digikam 5.3 (currently using 4.14 on a Ubuntu 
16.04 PC). So far the upgrade went smooth.

And **finally** video playback (broken in 5.2) and video thumbnails 
(broken since 4.1x) work!
Thank you to all involved! :-)

I have a few questions though, Those might not be bugs but rather 
settings problems, but I'd appreciate any help.

  * First of all, I can't seem to *change the **UI fonts*. I can change
    tree view and icon view fonts in Digikam's settings but not the font
    size of the UI  (tabs, menu, tooltips, face names on photos, etc). I
    installed "systemsettings" (KDE5) but in my Ubuntu Unity system it
    does not have a fonts option. Where/how can I set the rest of
    Digikam's UI fonts?

  * Interestingly, the*tree view font is not remembered* when I set it
    from within Digikam. This might actually be a bug.
    But while we're at it, I would rather have a "global font" option
    within Digikam than several different font options - for those not
    using KDE as a desktop this makes life much easier.

  * Then the *integration into Unity's global menu* doesn't work (yet).
    There is an 'appmenu-qt5' package but it doesn't seem to work. Any
    ideas?

  * Finally*some icons* (eg. in the settings sidebar) are still missing.
    This might be a packaging option.

Maybe somebody here has an idea? I'd appreciate any help.

Next, I'll try Digikam 5.3 on OS X where I plan to use it long term.

Thanks!