I would like to disable ligatures like ff and fi (“Office”, “Profile”) at view and print.
Ligatures are used inside libreoffice since 4.1, I have some users using 4.0 because of this problem.
Ligatures are handled at the font level (ICU layout engine in LO) but depend on several system technologies (refer this answer). If you use a font that does not support ligatures (e.g., Liberation Serif) then no ligatures will be substituted. There is not option in LO that I know of for turning of automatic ligature substitution.