10 Things in Opera that piss me off

In no particular order. Some major some minor, but all annoying. I currently use v9.21/MSI in Windows Vista Ultimate, on a P4 3GHz (Hyperthreaded) with 2GB RAM.

• In Vista only, exiting Opera will leave opera.exe in memory taking 100% of your CPU. Nice. It may remove itself after 5, 10, 15 minutes or more, but then it may not, so I simply End Task on it after about 30 seconds to un-cripple the machine. This didn't happen in XP, where with rare exception it would remove itself within 30 seconds. The only way to avoid this issue in Vista is if you run Opera very briefly with only a few tabs, which is not realistic. No other app I have does this. Known problem since February 2007.
• In Vista only, Opera will "pause" for about 5 seconds at random times throughout the day. When it does, its title bar will usually say "Not responding."  Apparently, this coincides with Opera writing out a small .TMP file to its profile directory, which never posed a problem in XP. No other app I have does this. Known problem since February 2007.
• Obscenely inefficient use of disk resources. Fire up Process Monitor some time and watch Opera go absolutely mad with disk and Registry accesses. I've never seen a program that can compare. My I/O Writes, for example, are typically around 50 million by the time I close Opera out every night. Sad.
• Making changes in Preferences--or even viewing some areas--can be agonizingly slow. A few choke points within Preferences include: Manage Cookies, Manage Site Preferences, and OK'g out after having made even a minor change. 
• Apropos of nothing (hey!) Opera will "permanently" highlight random pieces of text on a page. There's no way to un-highlight the text short of refreshing the page. There are reports of this happening since early builds of v9.0 in early 2006.
• No support for major add-on programs like the essential password manager Roboform, which works with numerous other browsers, such as the legendary "3B Browser" and "Flock."  Roboform is particularly necessary because Opera's own password manager, Wand, is so pathetic. Support for such add-ons has been a requested feature for years.
• No support for in-line Autocomplete in fields, similar to the feature in IE, FF, and every other browser made this decade (most likely). No, I'm not talking about the few things that you can pre-program into Wand, but Opera being able to recall what you've typed into any previous field on a Web page. I waste a little time every day by Opera not having this feature. This has been a requested feature for years.
• Inability to recall a list of recent searches in the Search box on the address bar (Google, etc). Of course it should be able to do it; of course it doesn't. I'll cheat by making this a two-fer and suggest that the Search box should also have the ability to auto-suggest items as you type them in, just like FF does.
• Support for very few typed-in URLs, such that a site you know you visited the day before yesterday isn't recognized when you begin to type it into the Address bar, forcing you to type in the entire address. But there's a # of "Addresses" section available in the History section of Preferences, you say?  Yes, there is, but when you increase it much beyond the default, it exacts a terrible toll on Opera's startup time. IE and FF can remember weeks on end of addresses with no impact on performance.
• Why is it when you "Find" an item on a page, whether you use the traditional Ctrl-F or the newer inline find, that it never tells you when you've found the last item?  Wouldn't that be more useful than silently cycling back to the beginning, leaving it up to you to notice?  Apparently not.

You didn't think that was all, did you?  These were just the first 10 off the top of my head. There will be more to come.