Assertion:
Netscape 4+ allows some Character-level formatting to be applied to the contents of this form field. These physical formatting elements (along with virtual formatting elements that are rendered identically, such as EM and I) apply to this form field: I, U, TT, S, STRIKE, SUB, SUP, BIG, SMALL, FONT SIZE and FONT FACE.

Input Type=File fields, with physical formatting elements enclosing them:
BehaviorExample
Plain filler text filler text
B filler text filler text
I filler text filler text
U filler text filler text
TT filler text filler text
S filler text filler text
STRIKE filler text filler text
SUB filler text filler text
SUP filler text filler text
BIG filler text filler text
SMALL filler text filler text
EM filler text filler text
STRONG filler text filler text
FONT SIZE (6) filler text filler text
FONT COLOR ("green") filler text filler text
FONT FACE ("verdana, georgia") filler text filler text