Opera caches webpages that you have already visited to improve the speed of the browser.
Nevertheless, starting with the 9.x version, Opera does, by default, send a request to the website to ask if anything has changed, and if so, it loads the new items. This of course is not a bad thing as it assures that you have the most up-to-date webpage to look at. But sometimes this can be “too much of a good thing”. In particular when you use the back button. Indeed, if you’re using the back button, that means that you were just there a few minutes ago, and the chance of something new AND important (i.e. not ads) being there is virtually nil.
For example, go to the New York Times and click on any article, and then on your back button. Did you see how there was a slight pause during which certain elements were reloaded? That’s because the NY Times site “told” Opera that there was new stuff, so Opera loaded the new things in. But I’ll bet a million bucks (uuh, that’s just a figure of speech) that the only thing new was the ads.
What we’re going to do is tell Opera to simply reload what it had previously cached, without checking for new items from the server. The result is that the back button takes you instantly and exactly to where you were, without the lag provoked by the renewing of content. I find that this really enhances my web-surfing experience.
Now before doing this, the only thing to take into consideration is if this seems right for you. If by chance you frequently visit websites that do change real content every minute or so, this is probably not a good idea for you. But for the rest of us, there really is no down-side to doing this. When you come back to the New York Times later, or tomorrow, Opera is going to reload everything anyway because the “check if cached page is updated” limit has been reached (by default 5 minutes; see Tools>Preferences>Advanced>History).
So what do ‘ya say? Let’s make Opera feel even faster.
Here’s how to do it
1) Open a new tab, so that you can keep this one open too.
2) Type “opera:config” in your address bar (without the quotation marks) and hit “Enter”. This opens your “Preference editor”, commonly called the ‘config menu’.
3) Scroll down a bit and click on “User Prefs”.
4) Scroll down even more to find a line called “History Navigation Mode”.
5) In the box, type in (or choose with the arrows) the number “3” (no quotes). This is the number for what is officially called “fast history navigation”
Scrrrrrooooll down again and click on “Save”, then “OK” in the confirmation dialog.
Go ahead and restart Opera just for the form, and then go back to the NY Times to see the difference in performance. I think you’ll be impressed.
For the official low-down check out this article in the Opera Knowledge base as a starting point.