Grime on windows, only visible when wet

I can't seem to get rid of this, its only visible when wet but its on every window including the windscreen.

I've tried claybar, 0000 steel wool and white vinegar spray.

Any ideas what it could be and what my next steps are?

I can't seem to get rid of this, its only visible when wet but its on every window including the windscreen.

I've tried claybar, 0000 steel wool and white vinegar spray.

Any ideas what it could be and what my next steps are?