Panel is sometimes transparent depending on compositor settings. I played with the settings of the compositor (scale method, rendering backend) and suddently the panel become normal (opaque).
When it's transparent depending on the wallpaper the text can become unreadable.
Steps to Reproduce:
1. Select breeze theme
2. Change compositor settings
Panel is transparent
Panel is opaque
I'm on Netrunner 16 with Nvidia drivers 349.16
does it happen from startup or just after changing theme/settings?
By default Netrunner have a semi transparent theme (not breeze) so it's just after choosing breeze theme that happen. Here you can have more infos :
Created attachment 93000 [details]
Breeze wrongly translucent
I see an article on phoronix with desktop screenshots on Fedora and the panel is too transparent too with breeze.
If I enable the contrast effect the panel become normal
Thus bug is related to this one :
Git commit d65c0ed1d07b4fb09643c9401a6697db1282d89e by Kai Uwe Broulik.
Committed on 08/06/2015 at 15:30.
Pushed by broulik into branch 'master'.
Bind translucent theme to background contrast rather than blur effect
Only the background contrast effect provides real contrast for contents, the blur effect
doesn't improve readability that much; so we now use the translucent theme only when we
have the background contrast effect. This significantly improves readability.
CHANGELOG: An opaque theme is now used when only the blur effect is available
Related: bug 342934
M +12 -15 src/plasma/private/theme_p.cpp
M +2 -3 src/plasma/private/theme_p.h
How do I get back my transparency now? I liked how it was with blur effect. Now I have 0 transparency and I can't seem to find option to turn it back on. I have blur effect on, it works fine on other themes.
Find a transparent theme on kde-look. Breeze with the transparency can be found here:
http://kde-look.org/content/show.php?content=170623 it is just a case of overriding the one config file.
In your case it was transparent because of a bug. The theme assumed it was being blurred with this effect, falling back to an opaque one if this effect is not available.
Ideally if you want your theme to look different, it should be because you chose the theme to look different; not as a side effect of breaking something in kwin.
It's an option in kwin for performance reasons not aesthetics ones. It wouldn't be fair on others to have the theme change because they made a performance change. Plus having that as the "correct" way to change the theme would not be particularly discoverable.