Created attachment 182964 [details]
the error message

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SUMMARY
Move to New Folder is creating the folder/file paths wrong, or at least is what it seems.

STEPS TO REPRODUCE
1. right click a file
2. select move to new folder
3. give new folder a name and try to create it

OBSERVED RESULT
Dolphin gives an error message saying it can't create the folder.

EXPECTED RESULT
A new folder be created and the selected file moved to it.

SOFTWARE/OS VERSIONS
Windows: 
macOS: 
(available in the Info Center app, or by running `kinfo` in a terminal window)
Linux/KDE Plasma: Tumbleweed
KDE Plasma Version: 6.4.1
KDE Frameworks Version: 6.15
Qt Version: 6.9.1

ADDITIONAL INFORMATION
I was under the illusion that this was happening, without reason, only on two folders, and specially annoying because it's the two folders where I actually use this feature a few times each day.
But it's not the folders, what causes the problem is the files I'm trying to move.
Those two folders have files with names that causes the problem. Creating a folder with a file name that contains something like "_00:23:35_158" isn't allowed, right? That's the problem, it seems when a file have some forbidden characters in it's file name Dolphin gets confused and tries to use that file name for the name of the folder instead of the one you gave when Dolphin asked.

If I try to nove a file with a simpler file name than Dolphin is able to create a new folder and move the file to inside it.

See in the image I annexed with the error message?
The "/Test" which is the name of the new folder comes at the end, after the name of the file.
On the same image if I rename any of those files and remove the forbidden characters it works.

At least I think this is the problem, and I think it was working in version 25.4.1, yesterday morning it stopped working without reason (along with video previews on Info Panel). I checked and Dolphin is version 25.4.2, must have arrived when I was checking for updates without noticing.