When I create GCODE files using GCodeTools on new Inkscape 1.0 (64bit on Windows) , it is plotting every line twice on my pen plotter.
I have been checking all setting for the last two days and can't seem to find what's the issue :( 

I have followed the same method on Inkscape 0.95 just to check and it's working fine! Could anyone please tell if Need to look at any particular setting to avoid such double lines?

Here's some simple gcode for a rectangle generated with GCodeTools on Inkscape 1.0 :

%
(Header)
(Generated by gcodetools from Inkscape.)
(Using default header. To add your own header create file "header" in the output dir.)
M3
(Header end.)
G21 (All units in mm)

(Start cutting path id: rect3306)
(Change tool to Cone cutter)

G00 Z15.000000
G00 X11.034134 Y188.965866

G01 Z-1.000000 F1000.0(Penetrate)
G01 X188.965870 Y188.965866 Z-1.000000 F3000.000000
G01 X188.965870 Y11.034130 Z-1.000000
G01 X11.034134 Y11.034130 Z-1.000000
G01 X11.034134 Y188.965866 Z-1.000000
G00 Z15.000000

(End cutting path id: rect3306)


(Start cutting path id: rect3306)
(Change tool to Cone cutter)

G00 Z15.000000
G00 X11.034134 Y188.965866

G01 Z-1.000000 F1000.0(Penetrate)
G01 X188.965870 Y188.965866 Z-1.000000 F3000.000000
G01 X188.965870 Y11.034130 Z-1.000000
G01 X11.034134 Y11.034130 Z-1.000000
G01 X11.034134 Y188.965866 Z-1.000000
G00 Z15.000000

(End cutting path id: rect3306)


(Footer)
M5
G00 X0.0000 Y0.0000
M2
(Using default footer. To add your own footer create file "footer" in the output dir.)
(end)
%

Found a solution on another thread! Thanks Mike!
https://inkscape.org/forums/cutplot/path-to-gcode-duplicate-lines-wrong-number-of-passes-workaround/