SUMMARY
After upgrading Dolphin to 25.08.2, I am no longer able to copy local files to an SMB share via Dolphin. I get an error "Access denied".

STEPS TO REPRODUCE
1. Copy a file from local computer
2. Navigate to SMB share from Dolphin, e.g.: smb://buzz.local/Media/
3. Paste

OBSERVED RESULT
Dolphin gives error message: "Access denied. Could not write to smb://buzz.local/Media."

EXPECTED RESULT
File should paste to folder on SMB share.

SOFTWARE/OS VERSIONS
Operating System: Arch Linux 
KDE Plasma Version: 6.4.5
KDE Frameworks Version: 6.19.0
Qt Version: 6.10.0
Kernel Version: 6.17.2-arch1-1 (64-bit)


ADDITIONAL INFORMATION
This worked with dolphin 25.08.1. I updated arch a few days ago, bringing dolphin to 25.08.2. I rebooted after updating all packages, and was immediately no longer able to paste files to the folder on my SMB server.

I can still upload the file manually with smbclient, so the issue seems to be with Dolphin:
1. smbclient //buzz.local/Media -U '%' -N
2. put file.txt

The SMB server is configured to allow guest access (guest ok = yes). I believe Dolphin is connecting as guest (I don't recall ever typing a username/password into Dolphin for this).