Parking long term with slide out "almost out".

I have 2 slides and they are both different. One is straight in-n-out with rubber gaskets that seal it the entire time regardless of its position. The other has a little ramp that it slides down into just prior to full extension. That's the only thing that seals it. If that slideout is not fully in or out, it's not sealed. However, the structure of the entire RV isn't designed for a slide to not be fully extended.