I used Gentoo's live ebuilds to install Frameworks 5 and Plasma 5's master branches. After some... several... ok, many hours compiling things Plasma 5 was installed and then I had my first surprise: I need kwallet 4 installed to import my secrets into kwallet 5, but I had uninstalled it before start compiling Plasma 5. Solution: compile kwallet 4 :-/ and try again. However, it was not that simple.
I used to use kwallet 4.14.2 (Gentoo's unstable version) but I installed 4.12.5 (Gentoo's stable version) without kdepimlibs installed. There are two problems with what I did: 1. kwallet uses a different file format when compiled with kdepimlibs installed. Since it was not installed kwallet 4 failed to open my wallet with "Unsupported file format version" error. Desperation started growing into my heart (my secrets, my precious secrets...). Looking at kwallet's source code (I love open source programs for allowing me to do that) I noticed that I needed to recompile it against kdepimlibs. So I did and... it did not work, the same "Unsupported file format version" error message appeared. 2. Looking into kwallet's git log I noticed that the file format's version changed between kwallet 4.12.5 and 4.14.2. I recompiled kwallet 4.14.2 and then kwallet 5 was able to import my old wallet :-). Tip of the day: do not uninstall Plasma 4 before importing your wallet. For Gentoo users that be a problem since akonadi-server's ebuild is configured to prevent compiling both qt4 and qt5 versions and akonadi-server is a dependency to compile kdepimlibs. I had to force (emerge --nodeps) Gentoo to compile kdelibs, akonadi-server, kdepimlibs and kwallet ebuilds to solve this problem.
With my wallet imported I though I had finished with that. However, Google Chrome did not list/show any of my secrets. The problem: Chrome uses the old dbus names org.kde.kwalletd and /modules/kwalletd instead of org.kde.kwalletd5 and /modules/kwalletd5. At least for now I decided to recompile kwallet 5 to use the old names, it works. Maybe we should add a command line option to make kwallet5 to also register those old names for backward compatibility.
After configuring my personal options in systemsettings my Plasma 5 desktop looks as productive as my old Plasma 4 desktop, which by the way I completely removed after fixing the kwallet issue. I still miss some applications such as Amarok, Digikam, Superkaramba (I created four applets for it that I would like to keep using). Two others, kdialog and polkit-kde-agent, are already ported to Plasma 5 but there is no ebuild for then, so I created the ebuilds and installed them.
polkit-kde-agent is necessary to allow Plasma NM to read secrets from system connections, which are stored in NetworkManager. It is a important program not only for me but for anybody that uses Plasma NM. After compiling it it did not work at first (always crashing). I had to apply this patch from reviewboard to fix the crashes.
To replace Amarok I recompiled Vlc to enable its qt plugin, which is already ported to Qt5 but Vlc compilation system insisted in using Qt4's include and libs even though it detected Qt5. For that reason when g++ tried to find QtWidgets' includes it failed. QtWidgets does not exist in Qt4. My solution was to export those two variables before compiling Vlc:
export QT_CFLAGS=$(pkg-config Qt5Widgets --cflags)
export QT_LIBS=$(pkg-config Qt5Widgets --libs
export QT_LIBS=$(pkg-config Qt5Widgets --libs
Sorry to the bashism in the line aboves, but it makes things shorter :-P
Vlc works, but crashes everytime it quits, not a big problem except that it never saves may playlist :-/ I still can press Ctrl+1 to make it load the first directory in the recent used list. I had to tweak my qdbus script to make my global shortcuts for play previous/pause/play next song to work with Vlc. Now it works almost as Amarok, except for the fancy features such as tablatures, lyrics, playlist sorting that I used to use from time to time. For the time being it will suffice. By the way, what is happening (or not happening) with Amarok? The lastest release was more than a year ago. Will it be ported to Plasma 5? Is there a Plasma 5 replacement for it?
One feature I missed since yesterday was the hability to select "shutdown computer" from leave dialog. Being the one that ported the old QWidget based shutdown dialog to Qml I expected the new dialog to be located in /usr/share/apps/ksmserver/themes/default, but now it is located in /usr/share/plasma/look-and-feel/org.kde.breeze.desktop/contents/logout/Logout.qml. Plasma 4's shutdown dialog theme is still in /usr/share/apps/ksmserver/themes/. After digging into ksmserver and libkworkspace's source codes I figured out that using kwrapper5 with ksmserver prevents shutdown and restart buttons from appearing in the shutdown dialog. The problem is that org.freedesktop.ConsoleKit.Manager.CanStop always return false when ksmserver is started through kwrapper5. I had to edit startkde script to do not use kwrapper5. OBS: I am using sddm and consolekit.
There are some random crashes here in there, but Plasma 5 is usable for what I need. Now I am ready to start fixing Plasma 5 issues :-)