In addition to large numbers of minor code tweaks (we count over 200), Opera 5.1 adds the following:
Flash. Opera now includes the Flash Plugin already "plugged in".
Opera Skins [searchengineworld.com]. Opera now sports the start of a skinning system. Users can customize the button bar backgrounds (main toolbar, xfer window, mail window, mdi surf bar) as well as the app space background (under mdi windows). Right click on an image to use as background or as foreground (buttons) and under the preferences options for "windows".
New MDI system. A subtle but powerful change has occurred. MDI windows may now be maximized while new windows are opened on top of them. This addresses the long standing complaint of Popup windows causing windows underneath to tile or cascade. If you don't like it, you can switch by adding Classic MDI = 0 to your [User Prefs] section of the Opera.ini file.
New status bar popup. An option for full screen mode to allow users to see progress information while the page is maximized. In your "User Prefs" section of the Opera.ini add: "Show Progress As Popup=1" to enable or use the Preferences option "show progress inside of address bar" to enable.
Install Changes. Changes to the install screen bitmap, a new install option to add Opera to the quick launch bar, and to start Opera when finished have been added.
Reload and Stop. The reload button is now replaced with a stop button while the page is being loaded.
Mouse Update. A option for mouse navigation gestures. Right click and drag left or right to go forward or backward. Drag and hold over a link to open the link in a new window. Drag downward while on a blank space to open a new window. You may turn it all off in preferences under accessiblity. Also mouse button reversing for lefties!
Mail Window Updates. New mail window look with the ability to show headers.
Email Font. By Popular demand: the email and news editor font now defaults to Fixed Pitch! Yeah!
Personal Data Removal Opera now sports an enhanced "delete all private data" dialog. You can now selectably delete: Global History, Visited Links, Temporary Cookies, Persistent Cookies, Mail and mail account Passwords.
Unfeatures: The email client can now be removed from the screen with Show E-mail Client=0 in your User Prefs section of the opera.ini (dll remains). You may also disable news and and instant messaging by adding "News Client=0" and "Show IM Client=0" in User Prefs section of Opera.ini.
.win file Bookmarking! You can now Bookmark .win files! This means entire groups of sites can be opened with a single click and in the same screen locations. Excellent for usenet News.
New preferences options: Many new options are present in the Opera preferences. Support for Skins, New Windows menu options, support for the mouse gestures, progress within status bar, and much more.
URL's in address bar history! You can now get URL's (vs titles) in the url address bar history. ...waves to the Opera crowd.
Desktop Wallpaper setter. Opera [opera.com] now has one of those nifty "right click on graphic" to set as desktop wallpaper images options