Exponents of variables become unreadable on the console using scilab 6.1.1

Reported by pierre perrichon (@perrichonpierre58)

BUG DESCRIPTION:
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Exponents of variables become unreadable on the console using scilab 6.1.1

Example is here provided with scilab 5.5.2 & 6.1.1 using the same preferences (monospaced 13 plain) in scilab console

ERROR LOG:
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none

HOW TO REPRODUCE THE BUG:
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Enter in scilab 5.5.2 and 6.1.1:

r = poly([-1-%i -1+2*%i 0],'s',"roots")


OTHER INFORMATION:
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 See also "Photo of the bug" in attached file, and transfer functions