When using calibre and similar applications that routinely interact with the web I am often irritated by the fact that they make use of the primary instance of the default web browser.
So, I was wondering if it would be feasible to add a preference to calibre (checkbox setting default off) that would have it create a fresh instance of the default browser at start up (i.e. do the equivalent of a Shift+click on a Windows taskbar icon) and use that for all web links (http://, https://, etc) - e.g. starting the server, Identifier links, web links on comments and similar. When calibre terminates it would close the browser instance it created at start-up.
Known con: secondary instances of Firefox don't get pinned tabs
BR
Bugger: I always forget the "Indifferent" option.