Paste Path Effect design makes it easy for effect authors to break, producing longstanding bugs in several different effects

Summary:

Path|Paste Path Effect of object containing 'Roughen' LPE will reset the 'Roughen' params on the original object.

Steps to reproduce:

• open Inkscape
• draw simple 2-segment Bezier; Fill:none, Stroke:Black, 3 clicks and carriage return
• add Roughen LPE, change params from defaults (e.g., set Max segment size to 2.0)
• draw another 2-segment Bezier; 3 clicks and carriage return
• select first Bezier and copy (Ctrl-C)
• select second Bezier and paste effects ('&')

What happened?

Roughen params on first object change when you paste into second. I also see some new param values "invented" in the second object, the one being pasted to.

What should have happened?

Pasting effects should never alter original object. Pasting should faithfully copy values from the originating object LPE.

Version info

Inkscape 1.3-dev (0727623fba, 2022-05-28)

    GLib version:     2.72.1
    GTK version:      3.24.34
    glibmm version:   2.66.4
    gtkmm version:    3.24.6
    libxml2 version:  2.9.14
    libxslt version:  1.1.35
    Cairo version:    1.17.6
    Pango version:    1.50.7
    HarfBuzz version: 4.3.0

    OS version:       Windows 10 21H1