documentclass[10pt,openright,twoside,a5paper]{memoir}
usepackage[english]{babel}

usepackage[showframe]{geometry}
setlength{parindent}{1.6cm}

begin{document}

frenchspacing
textbf{textbf: (encoding: T1, family: cmr, series: bx, shape: n, size: 10.5, baseline: 11.0pt)}

end{document}

D:test2.tex:10: Overfull hbox (5.92477pt too wide) in paragraph at lines 10--11[]OT1/cmr/bx/n/10 textbf: (en-cod-ing: T1, fam-ily: cmr, se-ries: bx, shape: