For my input, which can either have classname=\"half\" or \"half.not-placeholder-value\", Firebug shows both inputs to have a set, fixed width of
classname=\"half\"
\"half.not-placeholder-value\"
Use IE8 css with width? First part targets IE, second part undoes it for IE9+.
width
input.half, input.half.not-placeholder-value { max-width: 25em; width:25em\9; /* IE 8 */ } :root input.half, input.half.not-placeholder-value { width:inherit\9; /* IE 9+ */ }