Curve in Rubber Stretch is not as strong

When I try to apply Rubber Stretch extension on a path, the strength parameter is taken into account but the curve parameter has no effect on the final result.

Inkscape: 1.0 (4035a4fb49, 2020-05-01)
Operating System: Manjaro Linux 
KDE Plasma Version: 5.18.5
KDE Frameworks Version: 5.70.0
Qt Version: 5.15.0
Kernel Version: 5.7.0-3-MANJARO
OS Type: 64-bit

Edited Jul 07, 2020 by Nathan Lee

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