When you select a tab in Dolphin, and have the filter bar open, the filter bar has focus. This means that when you copy a file in one tab, change to a different tab, then try to paste the file, it will paste the filename into the filter bar rather than pasting the file into the folder. To me at least it was not immediately obvious this is happening, it just seems like the folder suddenly went empty. This was not the behavior with previous Dolphin releases. Reproducible: Always Steps to Reproduce: 1. Enable the filter bar 2. Open a new tab 3. Select the previous tab Actual Results: The filter bar has focus. Expected Results: The file area has focus.
I experience the very similar issue. It arose after recent update to KDE 4.14.3 (Gentoo Linux). I do not use Filter Bar, but I keep Places panel enabled. The issue is just same: after switching between Dolphin tabs with a key combination, the file area loses focus in favor of Places panel. Even more, if I move to the Dolphin tab with automatically assigned Alt+x combination (if you have two tabs with folders 'a' and 'b' open, Dolphin will automatically enable Alt+a and Alt+b combinations to swich to them), file area loses focus as well. In fact, even if no panel or bar is open, the file area will still lose focus to some other UI element.
Thanks for the bug report and sorry for the late response (missed it somehow?!) This bug should be fixed in the 14.12 release of Dolphin (there is an unofficial patch for the 4.14 branch in bug 338892) I'll mark this bug as a duplicate of 338892 *** This bug has been marked as a duplicate of bug 338892 ***