This is a bug I fixed in 10.4.0. Sorry for the inconvinience! To work around it in earlier versions, evaluate the following block of code

InactiveDump`assembleInactiveSumProduct[{args_, disp_, interp_, char_,
    tag_, tooltip_, fmt_}] := 
  TemplateBox[args, tag, DisplayFunction -> Function[disp], 
    InterpretationFunction -> Function[interp], SyntaxForm -> char]

The SyntaxForm which specifies precendence for parenthesization was missing before 10.4.0.

This is a bug I fixed in 10.4.0. Sorry for the inconvenience! To work around it in earlier versions, evaluate the following block of code:

InactiveDump`assembleInactiveSumProduct[{args_, disp_, interp_, char_,
    tag_, tooltip_, fmt_}] := 
  TemplateBox[args, tag, DisplayFunction -> Function[disp], 
    InterpretationFunction -> Function[interp], SyntaxForm -> char]

The SyntaxForm which specifies precedence for parenthesization was missing before 10.4.0.

This is a bug I fixed in 10.4.0. Sorry for the inconvinience!

This is a bug I fixed in 10.4.0. Sorry for the inconvinience! To work around it in earlier versions, evaluate the following block of code

InactiveDump`assembleInactiveSumProduct[{args_, disp_, interp_, char_,
    tag_, tooltip_, fmt_}] := 
  TemplateBox[args, tag, DisplayFunction -> Function[disp], 
    InterpretationFunction -> Function[interp], SyntaxForm -> char]

The SyntaxForm which specifies precendence for parenthesization was missing before 10.4.0.