I have a problem on Kubuntu, the kick-starter (start menu thing) was transparent till today, now its not transparent anymore, and I didn't change any settings or so, all my theme things are like before (transparent windows and so on) just the kick-starter is not transparent anymore. How can I get the transparency back? I am on an Acer C7 notebook. I have another PC running ubuntu and there the kickstarter is transparent (with the same theme) oxygen black I think it's called.
There are a few things you can try:
Sometimes it's just an issue with plasma. You can restart it by striking alt-f2 and typing the following:
kquitapp plasma-desktop && sleep 2 && plasma-desktop
Please note that this method could potentially cause other issues. If this doesn't work, you can also try logging out and logging back in again.
Hope this helps.