Jorge from Sketch asked me to post my bug request here:
The plugins-List in Preferences is empty, despite installed plugins. One hour before I was updating my own plugin and installed the update by double-clicking on the *.sketchplugin file. Previously I set
defaults write ~/Library/Preferences/com.bohemiancoding.sketch3.plist AlwaysReloadScript -bool YES
defaults write ~/Library/Preferences/com.bohemiancoding.sketch3.beta.plist AlwaysReloadScript -bool YES
The old plugin was replaced (thats what the alert was telling me), but suddenly the plugins-list in preferences no longer lists my installed plugins (this bug is in the current stable release as well as in the current beta). I can see all the installed plugins via the menu-bar and they all seem to work fine.
Updates of the installed plugins do also show up in the Sketch Menubar on the right side and i'm able to install them via sketch runner.
Restarting Sketch (Beta) does not solve the problem
Stable Screenshot: https://www.dropbox.com/s/c33l4t0ed26cm3g/Latest%20Sketch%20Release.png?dl=0
Beta Screenshot: https://www.dropbox.com/s/7isv7e3khgnagch/Latest%20Sketch%20Beta.png?dl=0