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SUMMARY

My custom servicemenu .desktop files recently stopped working when their exec line uses shell parameter expansion like ${foo%.*} or even a simple ${foo} while $foo still works. Though  ${foo:-bar} does return the foo value, so I am at a loss at what is happening here.

I tried every way of quoting and escaping I could think of, the parameter expansion either returns empty or the exec line fails with syntax errors.

STEPS TO REPRODUCE
1. create a simple servicemenu .desktop file with Exec=foo="%f"; cp "$foo" "${foo%.*}x".copy
2. place the desktop file in ~/.local/share/kio/servicemenus
3. open a new dolphin window
4. create a file bar.txt
5. point the servicemenu action at it 

OBSERVED RESULT

a file named x.copy is created, meaning the parameter expansion returned empty

EXPECTED RESULT

a file named bar.copy should be created

SOFTWARE/OS VERSIONS
Windows: 
macOS: 
Linux/KDE Plasma: 
(available in About System)
KDE Plasma Version: 6.0.5
KDE Frameworks Version: 6.3.0 
Qt Version: 6.7.1

ADDITIONAL INFORMATION

:~> cat .local/share/kio/servicemenus/testpe.desktop
[Desktop Entry]
Encoding=UTF-8
MimeType=all/all
Type=Service
Actions=copyPE
TryExec=cp

[Desktop Action copyPE]
Name=Copy with param expansion
Icon=text
Exec= foo="%f"; cp "$foo" "${foo%.*}x".copy