Question: Plot edits disappear after I use Plot Options Toolbar

WC51 III
Maple 2015

With straight line selected in following plot, I right-click on plot and select Line → Line Width...  In Set line width dialog I toggle line width to 1 and click OK.

I have the changes I want, but if I choose Restart → Execute Worksheet all my changes are lost.  It is often easier to use the Plot Options Toolbar instead of hunting for Maple syntax to make changes in a plot graphic.  I'm wondering if there is a way to "lock" my plot edits so that they won't disappear as I continue working on a Maple worksheet?

restart;
with(plots);
eq1 := -y^3+x^2+x*y-7; eq2 := y = (8/9)*x-2/3;
implicitplot({eq1, eq2}, x = 0 .. 4, y = 0 .. 3, axis = [gridlines = [6, color = "MidnightBlue"]], size = [1/2, 1], axesfont = ["Roman", bold, 10], thickness = 3);