While holding down the Shift key, click two plot markers. - The second plot marker will become the owner of the plot line.
Remove a plot marker
While holding down the Alt key, click a plot marker. - The plot marker will be removed along with any plot lines it owns.
Plot 1
Plot 2
Click a plot icon:
to set the plot marker coluor you want to use
Set a plot line:
Remove only  plot lines
While holding down the Alt & the Shift  keys, click a plot marker. - The plot lines owned by the plot marker  will be removed.
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