This comparison is made by a Firefox supporter, so do not expect full impartiality or accuracy. However, you may be kind to point out any error, inaccuracy or incompleteness in the following chart. Any comments are appreciated.

Compare Firefox with IE/Maxthon/Opera
Firefox Internet Explorer Maxthon Opera
Popup Blocking Yes WinXP: with SP2 Yes Yes
Tabbed Browsing Yes NO Yes Yes. MDI
Default Download Folder Yes NO NO ?
Built-in Search Yes NO Yes Yes
Super DragAndGo Ext. Super DragAndGo NO Yes NO
Mouse Gestures Ext. NO Yes Yes
Ad Block Ext. Adblock NO Yes Yes. Reference
Themes/Skins Yes. Personalize your taste with other themes! ? Yes Yes
Extensions Yes. Customize your Firefox with hundreds of extensions! Yes Yes No
Boss Key Ext. Minimize to Tray(for Windows) NO Yes NO
Add Bookmark Here Ext. Add Bookmark Here NO Yes Yes
USB Drive-Friendly? Yes. Portable Firefox! NO ? ?
(Simplified)Chinese Localization Yes. Download it now! Yes Yes Yes
Web Standards Support Good Poor The same as IE. Maxthon is based on IE engine. Good
Security Excellent. "Safer, faster, better", "The browser you can trust!" Bad Can be configured to filter ActiveX script, however, security hole in IE can not be fixed in Maxthon. Excellent.
Cross-Plateform? Official builds for Windows, Linux, MacOS X and contributed builds for Solarix x86, Solarix Sparc, OS/2 and AIX. Only for Windows(What else do you expect?) Only for Windows. Maxthon is an add-on to IE. Windows, Solarix Sparc, QNX, OS/2, MacOS, Linux(Sparc, PowerPC,i386), FreeBSD i386, BeOS.
Free? Open Source Software You can call it "freeware" if you like, but never expect free Windows. Freeware? Adware