Firefox 2.0 uses tabs more aggressively than Firefox 1.5 did. In Firefox 1.5, if you clicked on a link that attempted to spawn a new window (not a popup, just another regular browser window), Firefox did as it was asked. Now it opens those links in a new tab in the current window. As before, if you open a URL from another application, it opens that link in a new tab in the foremost browser window.
I like tabs, so I’m generally OK with that behavior, except for one thing. Some of the time, I have a small window open, usually thanks to my Movable Type “quick post” bookmarklet. I never want the browser to open a new tab in that window. In fact, if it’s the only window that’s open, I would prefer the browser open a new window entirely. I expect most other users feel the same way.
Thinking like a programmer, this looks like a problem that could be solved cleverly through code. Basically, when deciding where to put the results of an “display URL in a new window/tab” action, the browser could examine the size of the open windows, and pick one that is the same size as a new window would be if you opened a new window from the file menu. There may even be a variable that could be checked to see whether a window was opened by normal means or opened as a custom-sized window from a web page, and only use “normal” windows.
Chances are I’m not the only person annoyed by this behavior. I’m going to do some digging today to see if I can find any existing solutions.