Renaming: adding shadows is one way to improve readability, but not necessarily the solution here. The problem is readability due to lack of contrast, not necessarily missing shadows.

FWIW, I intentionally left out visual frills initially hoping for VDG pronouncement on these things - we had standard APIs for text effects in Plasma 1 that are gone now; for consistency we need to come up with proper replacements rather than add individual solutions everywhere.

Can someone please CC the proper address for the VDG?

For text on unpredictable backgrounds, the ways I can think of dealing with this are:
1. Add a text background
2. Add a text shadow
3. Add a text outline

I'm open to other Ideas, but absent those, I'm partial to 1 or 2 depending on ease of implementation. I'm interested in developers thoughts on this since I think either approach will facilitate good visuals.

I'd say all of them have about similar complexity.

2.-3. most likely involve switching the text label to a custom C++ object - QML theoretically has a stock effects system for this, but I've never seen its drop shadow effect work correctly for FreeType-rasterized Text items on a variety of drivers, and it was slow as well. This is already the case for the Task Manager task button labels, which have a shadow/outline effect depending on the text color, implemented in C++.

1. Might require C++ as well, depending on whether the background should be clipped to actual line rects or the overall bounding box.

Could the VDG maybe iterate some mockups for what they think would:

(a) Fit in well with Breeze as top priority.
(b) Complement other similar use cases in the shell well (i.e. the consistent text effects issue).
(b) Have a generic-enough way of working that it could possibly be put under theme control to some degree.

*** Bug 336344 has been marked as a duplicate of this bug. ***

Git commit 4a6813eb5f312d317738c582979a0619bfb4be1a by Eike Hein.
Committed on 20/06/2014 at 01:41.
Pushed by hein into branch 'master'.

Configurable text color in containment case.

M  +3    -0    containments/folder/package/contents/config/main.xml
M  +42   -0    containments/folder/package/contents/ui/ConfigIcons.qml
M  +1    -1    containments/folder/package/contents/ui/ItemDelegate.qml

http://commits.kde.org/plasma-desktop/4a6813eb5f312d317738c582979a0619bfb4be1a

The change based on review request 118891 to add a text background has been committed (5819be4). 
The commit hook didn't close this bug since I don't have permissions on this bug report to do that. :-)

Hope this helps, and please let me know if there's anything else needed to close this bug.