#3471102: Unable to scroll component list
requested to merge issue/experience_builder-3471102:3471102-unable-to-scroll-component-list into 0.x
Making the component list scrollable by removing unnecessary code from an event handler that took over scrolling, then making the container of the list scrollable by fixing its height and adding overflow:auto. I also had to make sure preview thumbnails are rendered in a portal, otherwise overflow:auto causes trouble with those elements.
