I’m used to putting my laptop to sleep/hibernate, and often times, Firefox stays open in a single session, until I restart the machine eventually. However, I noted that some websites didn’t update automatically when their tabs were closed and re-opened later on, and that a click on the refresh button was needed in those cases.

To make cache work as it should when Firefox is left open for ages, modify the browser.cache.check_doc_frequency setting in about: config. Its values can be set as follows:

0 – once per session (default)
1 – every time
2 – never
3 – automatically

Changing the setting to 1 does the trick.

Those using Firefox version 3.0+ may have noticed a tooltip comes up when you hover on the url icon, providing some details about the domain you’re visiting. While possibly useful, this feature, enabled by default, effectively prevents usage of the toolbar bookmarks via drag&drop, if the target bookmark toolbar folder lies just under the address bar.

The solution is to disable the tooltip, by setting variable browser.chrome.toolbar_tips to false in about:config.