I am using the Neo keyboard layout, which uses all kinds of modifier keys to input all kinds of characters (e.g. Greek letters and mathematical symbols). It also has shift+Mod3+space mapped to Unicode 0A, no-break space. From time to time it happens that I mistakenly press these buttons (while entering a space between other symbols with the same modifier keys).
Unfortunately [Lua|Xe]TeX obeys these spaces as unbreakable spaces both in normal text and in mathmode (using
unicode-math). However my editor (vim) shows the symbol like a normal space, so it is impossible to see where I made a mistake.
Is there an easy way to tell [Lua|Xe]TeX to treat no-break spaces like normal spaces?