Script Summary: Adds a "Mark Read" or "Mark Unread" button to Gmail pages (active only when mail items are selected). This version fixes all wrapping issues, and allows to work even on GMail for Domains.
Note from script editor: I havent looked at this in years as gmail does what I need it to, but it's noted in a review that this no longer works. YMMV.
Gmail Mark Read Button fixed to prevent displayed items from wrapping.
This is achieved by shrinking the font size of the displayed items to 11px. If it still wraps, open the file in wordpad (notepad sucks), and do a search for 11px. Change that to a smaller number that suits your liking, although I wouldn't go below 8px, as it gets hard to read after that.