Manual demo "some kind of news": increasing text size causes calendar on the side bar to overlap with the main content

1. Open up "some kind of news" demo: http://build.fluidproject.org/infusion/tests/manual-tests/html/SomeKindOfNews.html
2. Click "show display preferences" to open up the preferences editor;
3. Increase the preference "text size";
4. The calendar on the sidebar expands beyond the sidebar area and overlaps with the main content.